Sarah Ferguson, Beatrice and Eugenie invited Jeffrey Epstein to Andrew’s 50th just days after he was released from prison

The former Duchess of York and her two children asked the convicted sex offender to come and celebrate “50 years of Papa/Andrew” and bring “presents, presence and your humour” to the event at St James’s Palace in London.

The trio informed him of the “suits and cocktail dresses” dress code and promised that an exclusive reception would feature some of her own “mysterious mischief”.

The latest batch of Epstein files revealed that Andrew’s private secretary Amanda Thirsk wrote the email in February 2010 inviting him to the 50th.

But it emerged today that Epstein was still invited even though he was convicted sex on sex trafficking charges after pleading guilty to soliciting sex from girls as young as 14, the Daily Mail reports.

It came as Epstein was in discussions with Andrew over clearing a $120,000 debt Ferguson accumulated.

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Replying to the email sent by Thirsk, Epstein simply wrote back “not able”. 

Documents released by the US Department of Justice last Friday showed Ferguson had told Epstein she wanted to marry him, and also discussed her daughters' love and sex lives with her "pillar" of strength, Epstein, over email.

She has not been seen in public since the scandal broke.

Files also showed the sex offender was asked to pay almost $15,000 for flights for Fergie, Beatrice and Eugenie to go to the US to visit him just 48 hours after his release from prison.

In the months after he left jail following a 13-month sentence for soliciting sex from girls as young as 14, Ferguson repeatedly told Epstein he should marry her.

That was in September 2009, five months before the party.

It also has also emerged that Beatrice, Eugenie and their mother were seemingly so close to Epstein that they visited him in Florida five days after his release. Epstein's assistant Lesley Groff emailed him asking him to approve payment for the Yorks' travel costs on July 24, 2009.

She wrote: "Regarding the flights for The Duchess and the girls from Heathrow to Miami and from NY to Heathrow: we are able to get the girls on economy round trip and The Duchess in business round trip.

"The girls flights total are $4835.94 and The Duchess' flights total $9244.16. Do I have your permission to purchase these tickets!?."

Documents claim the group met at Epstein's Palm Beach mansion, where the paedophile served vegetable lasagne prepared by a Parisian chef.

The meeting was then brought up again by Epstein over two years later, when he wrote to British lawyer Paul Tweed to complain about Ms Ferguson's failure to defend him publicly following his conviction.

Epstein appears to have repeatedly organised accommodation for Fergie in the US.

On one occasion on July 13, 2010, she replied: "Dear Jeffrey, yes I did need a second place for a week?

"And I thank you so much, but just as I predicted many, many months ago, the British press is ready to exterminate me, and it seems that PricewaterhouseCoopers and the palace system are not equipped to deal with all of this huge wave of negativity.

"Therefore I have to return to the UK, and be exterminated and face the thunderous music.

"I am now 1000 per cent being hung out to dry, just as I predicted you will see, the Press will have me exiled. I am totally on my own now.

"This is beyond scandalous and nobody can do anything. I cannot believe what this is all coming to.

"I have to return to face my judge and jury and be hung yet again."

The PwC were auditing her accounts at the time.

It later emerged that Epstein had paid off some of her debts - a move she would later describe as a "gigantic error".