This trip has played out just as Buckingham Palace had hopedpublished at 17:05 BST

17:05 BST

Daniela Relph
Senior royal correspondent

There was surely a sigh of relief from the King and Queen as they departed the White House after the official goodbye.

This has played just as Buckingham Palace and the UK government had hoped - the King had his say in that speech to Congress. He made his point without obviously upsetting his host.

The president’s love for the Royal Family seems undiminished.

As the King and Queen said their goodbyes to their hosts, the Queen and first lady could be seen talking, with the Queen pointing out something on her outfit.

She was showing Melania Trump the Tiffany brooch she was wearing. It had been a gift from the first lady during the Trumps' visit to the UK last September.

Farewell showed different approaches from the King and Trumppublished at 16:40 BST

16:40 BST

Daniela Relph
Senior royal correspondent

Image source, Reuters

The King and Queen's trip to Arlington National Cemetery follows shortly after their formal farewell with US President Donald Trump.

The official goodbye showed the different approaches of the president and the King.

Donald Trump was happy to chat in front of the camera. The King seemed less enchanted.

When the King was asked for a favourite moment from the trip by reporters - there was no clear reply. Just a smile - he was not going to be drawn into any public exchanges.

The visit to Arlington Cemetery - where he is at the moment - will be deeply meaningful for the King. As head of the UK Armed Forces, honouring those who’ve served is built into just about every state visit he embarks on.

Much of this trip has mirrored elements of trips to the US undertaken by the King’s mother - the late Queen Elizabeth II. When he laid a wreath at the Tomb of the Unknown Soldier today, he was walking in the footsteps of his mother who did the same during her first state visit to the US in 1957.

Image source, Reuters

After a brief pause, the royals then move away from the monument.

They pass a small crowd of onlookers, and up some stairs into a building.

US service members march in front of the building, carrying assorted flags as a drumbeat plays.

Image source, Getty Images

Image source, Reuters

The King is handed a wreath, which he lays at the foot of the Tomb of the Unknown Soldier. He stands briefly for a moment of remembrance.

The Queen then walks up to stand next to him. She's handed some flowers which she also lays at the foot of the monument.

Image source, Getty Images

Image source, Reuters

The King and Queen come to a stop. They're flanked by a military guard of honour while a Union Jack is carried behind them.

The UK and US national anthems are played by a military band, while the royals stand listening.

Image source, Getty Images

Stepping out of their car at the cemetery, the King and Queen are greeted by officials.

They spend a little while looking at a picture, before walking towards the Tomb of the Unknown Soldier.

Image source, Reuters

Following a short drive from the White House, the King and Queen have now arrived at Arlington National Cemetery.

A long motorcade could be seen driving down the road to the cemetery.

Felicity Baker
Royal producer

Here at Arlington National Cemetery, the royals will lay a wreath and posy at the Tomb of the Unknown Soldier - to honour the US and UK’s military partnership.

They’ll also view the Canadian Cross of Sacrifice and meet groups of serving military personnel from the UK, Canada, Australia and New Zealand.

Zaineb Sharif
Reporting from Arlington National Cemetery

Image source, BBC / Zaineb Sharif

I’m standing just outside Arlington National Cemetery, where preparations are underway for the arrival of the King and Queen.

They'll be here shortly - as they conclude their final day of their four-day state visit.

Security has tightened as Secret Service officers and dogs have been going around sniffing cars in the area.

I have just spoken to someone who was inside the cemetery, who says that many visitors are not aware that the King and Queen will be there.

Their visit is expected to include a wreath-laying ceremony honouring fallen service members.

The King and Queen are expected to arrive there imminently - watch live at the top of the page.

Image source, Reuters

Shortly after the car drives off, Donald Trump tells the gathered press: "Great people."

"We need more people like that in our country," he says.

The US president thanks the press, and then he and the first lady turn around and go back inside the building.

Image source, Getty Images

A few minutes later, the group emerges from the White House.

Standing in the doorway, the King and Trump appear to have a brief conversation, and they continue chatting as they make their way down the red carpet towards the car.

They exchange goodbyes before the King and Queen enter the car to be driven away.

Image source, Getty Images

President Trump points towards the King and tells the gathered press: "Great king."

"The greatest king in my book," he adds.

The group pose for pictures before heading inside.

Image source, Reuters

Image source, Getty Images

Image source, Pool/Getty Images

Image source, Getty Images

Image source, Getty Images

The King and Queen have just arrived at the White House.

They leave a black car, are are greeted by President Trump and First Lady Melania Trump.

Image source, Reuters

President Donald Trump and First Lady Melania Trump are about to say a formal farewell to King Charles and Queen Camilla.

Outside the White House - on the South Portico - the scene is currently set with a red carpet and flags from both countries.

We expect to see them imminently - you can watch live at the top of the page.

From addressing Congress, to feeding chickens in New York, and to meeting Lionel Ritchie - it has been a busy state visit for King Charles and Queen Camilla.

Image source, Reuters

Image source, Reuters

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images

Image source, Reuters

The King and Queen will soon be greeted by the president and first lady for a formal farewell on the final day of their state visit to the United States.

The royals will then head to neighbouring Virginia, where they will lay a wreath at Arlington National Cemetery, before attending a party to celebrate the United States' 250th birthday.

Earlier in the pomp-filled four-day trip, the King delivered an address to Congress - which was greeted by a standing ovation - and was treated to a lavish state dinner.

After leaving the US later, the King will pay a visit to Bermuda - a British overseas territory, where he is also head of state - before returning to the UK.

We're now resuming our live coverage of the state visit, and will bring you updates in this page.

Want more from the royal visit to the US? Here's where to read and watch the best material on the BBC News website.

• The King's address to Congress, where his mother spoke 35 years ago, received a standing ovation - watch the key sections here
• Our royal correspondent Sean Coughlan writes from the Capitol Building in Washington that the speech marked the biggest diplomatic moment of King Charles' reign - get his analysis here
• Some parts of his speech may have buoyed Democrats and raised eyebrows in the White House, writes our North America correspondent - read his five key takeaways
• Yesterday's fanfare culminated in a glitzy state dinner with high-profile guests, including golfer Rory McIlroy and Amazon founder Jeff Bezos - see the best pictures here
• Trump paid homage to his Scottish mother's roots, recalling that she described King Charles as "cute" - find out more here
• Our chief political correspondent Henry Zeffman has taken the temperature in Westminster - here is how the visit it being viewed

• We also have take on the night's fashion and jokes littered throughout the president and King's speeches

Image source, Reuters

From all the grandeur in Washington, will better relations between the US and UK emerge?

The British government certainly hopes so, and the reception the royals received will doubtless encourage ministers and officials.

A military ceremony and speech by Donald Trump kicked off celebrations yesterday, with the president saying Americans have had "no closer friends than the British".

The King's address to the Congress then called for continued cooperation between London and Washington on defence matters, including supporting Ukraine and resisting calls for the UK-US alliance to "become ever more inward-looking".

But eyebrows were raised later in the evening.

During a state dinner, Trump suggested the King was supportive of his Iran policy - to which Buckingham Palace said the monarch is simply "naturally mindful" of the British government's established position on nuclear weapons.

The King emphasised his earlier support of Nato during his toast at a state dinner, a message Downing Street will hope sticks in the president's head.

Commentators on both sides of the pond have hailed the King and Queen's visit as a diplomatic success - but questions remain around whether the positive mood will survive after the royals set off for New York.

Henry Zeffman
Chief political correspondent

There is definite relief and happiness in government that the King’s state visit has gone so well.

That would of course be the case at any time, but especially so given transatlantic relations have been so strained of late.

However, among figures in government there is also realism.

Just because Donald Trump has spoken so affectionately of Britain in the presence of the King, it does not mean his frustration with Sir Keir Starmer and the British government is likely to abate.

After all, Trump’s state visit last year to the UK went off without a hitch — including a press conference alongside Starmer at Chequers where the president was on his best behaviour.

Nevertheless, within a few months the differences on foreign policy between both leaders began to show more and more prominently.

Of course, for all that Starmer would no doubt prefer not to be derided on social media by the US president periodically, he has sought to turn their dispute to his advantage politically, arguing that it shows he will stand up for the national interest in a way his opponents would not.

Don’t expect the PM to cease making that argument anytime soon, whatever the lingering warmth from this royal tour.

Image source, EPA/Shutterstock

It's very early in the US but later we'll see King Charles and Queen Camilla visiting New York, where they'll meet families of victims of the 9/11 attacks ahead of the 25th anniversary later this year.

The King will then visit a grassroots urban farming initiative that works to mentor children affected by food insecurity.

The Queen will celebrate British and American literature at an event with The Queen's Reading Room, the charity she founded, alongside high-profile authors.

Later, the King will meet business and financial leaders at an event designed to promote transatlantic trade.

Then there will be a reception to celebrate the work of the The King's Trust charity, which is expected to focus on cultural and creative links between the US and UK.