Melania Trump has threatened to sue Hunter Biden for more than $1bn (£736.5m) in damages if he does not retract comments linking her to Jeffrey Epstein.

Mr Biden, who is the son of former US president Joe Biden, alleged in an interview this month that sex trafficker Epstein introduced the first lady to President Donald Trump.

“Epstein introduced Melania to Trump. The connections are, like, so wide and deep,” he claimed.

Ms Trump’s lawyer labelled the comments false, defamatory and “extremely salacious” in a letter to Mr Biden.

Her lawyer wrote that the first lady suffered “overwhelming financial and reputational harm” as the claims were widely discussed on social media and reported by media around the world.

The president and first lady previously said they were introduced by modelling agent Paolo Zampolli at a New York Fashion Week party in 1998.

Mr Biden attributed the claim that Epstein introduced the couple to author Michael Wolff, who was accused by Mr Trump of making up stories to sell books in June and was dubbed a “third-rate reporter” by the president.

The former president’s son doubled down on his remarks in a follow-up interview with the same YouTube outlet, Channel 5 with Andrew Callaghan, entitled “Hunter Biden Apology”.

Asked if he would apologise to the first lady, Mr Biden responded: “F*** that – that’s not going to happen.”

He added: “I don’t think these threats of lawsuits add up to anything other than designed distraction.”

Ms Trump’s threat to sue Mr Biden echoes a strategy employed by her husband, who has aggressively used legal action to go after critics.

Public figures like the Trumps must meet a high bar to succeed in a defamation suit like the one that could be brought by the first lady if she follows through with her threat.

In his initial interview, Mr Biden also hit out at “elites” and others in the Democratic Party, who he claims undermined his father before he dropped out of last year’s race for president.

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The letter threatening legal action against Mr Biden is dated 6 August and was first reported by Fox News Digital.

It was addressed to Abbe Lowell, a lawyer who has represented Mr Biden in his criminal cases. Mr Lowell has not yet commented on the letter.

Read more: What you need to know about Trump, Epstein and the MAGA controversy

This comes as pressure on the White House to release the Epstein files has been mounting for weeks, after he made a complete U-turn on his administration’s promise to release more information publicly.

The US Justice Department, which confirmed in July that it would not be releasing the files, said a review of the Epstein case had found “no incriminating ‘client list'” and “no credible evidence” the jailed financier – who killed himself in prison in 2019 – had blackmailed famous men.

Donald Trump and Vladimir Putin will meet for the first time in six years on Friday, with a possible deal to end the Ukraine war on the agenda.

Mr Trump has threatened “very severe consequences” if his Russian counterpart doesn’t agree to a ceasefire at the summit, being hosted at a remote US army base in snowy Anchorage, Alaska.

Follow latest updates from Ukraine war

But there are fears they will discuss a deal robbing Ukraine of the land currently occupied by Russia – something Volodymyr Zelenskyy has said he won’t accept.

Here’s what three of our correspondents think ahead of the much-anticipated face-to-face.

Putin’s legacy is at stake – he’ll want territory and more
By Ivor Bennett, Moscow correspondent, in Alaska

Putin doesn’t just want victory. He needs it.

Three and a half years after he ordered the invasion of Ukraine, this war has to end in a visible win for the Russian president. It can’t have been for nothing. His legacy is at stake.

So the only deal I think he’ll be willing to accept at Friday’s summit is one that secures Moscow’s goals.

These include territory (full control of the four Ukrainian regions which Russia has already claimed), permanent neutrality for Kyiv and limits on its armed forces.

I expect he’ll be trying to convince Trump that such a deal is the quickest path to peace. The only alternative, in Russia’s eyes, is an outright triumph on the battlefield.

I think Putin‘s hope is that the American president agrees with this view and then gives Ukraine a choice: accept our terms or go it alone without US support.

A deal like that might not be possible this week, but it may be in the future if Putin can give Trump something in return.

That’s why there’s been lots of talk from Moscow this week about all the lucrative business deals that can come from better US-Russia relations.

The Kremlin will want to use this opportunity to remind the White House of what else it can offer, apart from an end to the fighting.

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Ukraine would rather this summit not be happening
By Dominic Waghorn, international affairs editor, in Ukraine

Ukraine would far rather this meeting wasn’t happening.

Trump seemed to have lost patience with Putin and was about to hit Russia with more severe sanctions until he was distracted by the Russian leader’s suggestion that they meet.

Ukrainians say the Alaska summit rewards Putin by putting him back on the world stage.

But the meeting is happening, and they have to be realistic.

Most of all, they want a ceasefire before any negotiations can happen. Then they want the promise of security guarantees.

That is because they know that Putin may well come back for more even if peace does break out. They need to be able to defend themselves should that happen.

And they want the promise of reparations to rebuild their country, devastated by Putin’s wanton, unprovoked act of aggression.

There are billions of Russian roubles and assets frozen across the West. They want them released and sent their way.

What they fear is Trump being hoodwinked by Putin with the lure of profit from US-Russian relations being restored, regardless of Ukraine’s fate.

That would allow Russia to regain its strength, rearm and prepare for another round of fighting in a few years’ time.

Trump and his golf buddy-turned-negotiator Steve Witkoff appear to believe Putin might be satisfied with keeping some of the land he has taken by force.

Putin says he wants much more than that. He wants Ukraine to cease to exist as a country separate from Russia.

Any agreement short of that is only likely to be temporary.

Trump’s pride on the line – he has a reputation to restore
By Martha Kelner, US correspondent, in Alaska

As with anything Donald Trump does, he already has a picture in his mind.

The image of Trump shaking hands with the ultimate strongman leader, Vladimir Putin, on US soil calls to his vanity and love of an attention-grabbing moment.

There is also pride at stake.

Trump campaigned saying he would end the Russia-Ukraine war on his first day in office, so there is an element of him wanting to follow through on that promise to voters, even though it’s taken him 200-plus days in office and all he’s got so far is this meeting, without apparently any concessions on Putin’s end.

In Trump’s mind – and in the minds of many of his supporters – he is the master negotiator, the chief dealmaker, and he wants to bolster that reputation.

He is keen to further the notion that he negotiates in a different, more straightforward way than his predecessors and that it is paying dividends.

So far, despite sanctions on Russia, despite warnings and deadlines, the situation in Ukraine is only getting worse.

He’s hoping that this meeting, simply the act of sitting down with Putin, can change the tide.

The Russian president may have different ideas.

It’s official. Donald Trump will host the 2025 Kennedy Center Honors – Washington’s annual black-tie celebration of artistic achievement.

In previous years, occupants of the White House simply attended the event in the building named after President John F Kennedy.

Earlier this year, the US president sacked the board and installed himself as chairman and is threatening to put his own name on the door.

“GREAT nominees for the TRUMP/KENNEDY Center, whoops, I mean KENNEDY CENTER AWARDS…” he posted on his Truth Social platform.

Vowing that the show will be “non-woke”, he announced this year’s nominees – a stroll through Trump’s cultural sweet spot:

• George Strait, who’s branded the king of country music
• Sylvester Stallone, who, as Rocky Balboa, defeated the Cold War in a boxing ring
• Gloria Gaynor, whose “I will survive” could double as Trump’s campaign theme
• KISS, whose pyrotechnics will have the Secret Service on edge all evening
• And, wait for it, the British Broadway star, Michael Crawford

Crawford’s West End and Broadway career spans Barnum, The Woman in White and, of course, The Phantom Of The Opera..

The Phantom’s tendency to buy grand, chandelier-filled buildings, has won the approval of the real-estate mogul now remodelling the White House.

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But there’s something Americans might have missed – the character who made Michael Crawford a household name back home: Frank Spencer.

The star of the sitcom “Some Mothers Do ‘Ave ‘Em” was endlessly optimistic but completely hapless, and oblivious to his own incompetence.

Revealing that he would host the awards himself, just two days before he hosts Vladimir Putin, is quintessential Trump, the prime-time president.

But “Ooh Betty,” as Frank Spencer would say, when Donald Trump extols Michael Crawford, an icon of slapstick comedy, the script writes itself.