The child sex trafficking suspect, 59, is seen in a newly-emerged photograph sipping a drink while the three girls surround a City broker and his friend.
On the same night, next door at the Odeon Leicester Square, Prince Charles attended the premiere where he was seen arm in arm with its stars Drew Barrymore and Lucy Liu.
There is no suggestion the Prince of Wales was aware of Maxwell’s presence with the young girls.
But the photo raises fresh concerns about how close she and billionaire paedophile Jeffrey Epstein came to royal circles, with their links to Prince Andrew already under scrutiny.
The anonymous broker seen next to the alleged madam and the three young girls said he is ‘appalled’ at the thought of them targeting guests at the party.
He said: ‘The three girls came up to me and a friend and were being very flirtatious. They were in their late teens or early 20s.
‘One, who is on my right in the picture, seemed to be the leader and was asking us if we wanted to buy them drinks or go on somewhere.
‘The girl on my left was quieter and more nervous.
‘And the girl at the back was East European and also quiet. It seemed their questions were all to ascertain our wealth.’
The broker said no one was interested in the girls and after a few minutes they were ushered away by Maxwell.
A source found the photo while tidying their possessions and recalled Maxwell being annoyed with the girls for spending too long with certain guests before moving them along.
They said they discussed at the time whether the girls might have been escorts.
The Prince of Wales had made a speech for The Prince’s Trust on the night, which benefited from the premiere.
Just 18 days earlier, Maxwell was an alleged guest of Prince Andrew at a Los Angeles party hosted by BAFTA for the Charlie’s Angels film.
And a month later, Epstein and Maxwell joined the Duke of York in the Sandringham Estate for a pheasant shoot.
The Prince’s Trust said it did not organise the party attended by Maxwell and had ‘no data’ about the event.
It comes amid rumours Maxwell could start ‘naming names’ if she is found guilty of sex trafficking charges this week.
Closing arguments in Maxwell’s trial begin tomorrow, with the jury likely to retire that evening.
A legal source connected with the case told The Mail on Sunday that with the Manhattan court breaking for Christmas at the end of Wednesday, a verdict this week is ‘highly likely’, adding: ‘The jury won’t want this hanging over them over Christmas, so lawyers on both sides expect a verdict this week.’
Maxwell denies all six charges linked to grooming underage girls for abuse by the late paedophile Jeffrey Epstein.
However, the source said if she is convicted – and facing up to 70 years in prison – she might co-operate with the US Government in exchange for a reduced sentence or better jail conditions.
‘This could be bad news for Prince Andrew and other high-profile men who hung out with Ghislaine and Jeffrey Epstein,’ the source said.
‘It is possible she will begin to co-operate and tell what she knows in an attempt to lessen her jail term. We know that prosecutors are looking at other co-conspirators in connection with Jeffrey Epstein’s child sex ring. Ghislaine undoubtedly possesses information which could assist prosecutors in other cases. If she decides to co-operate, her testimony could be devastating. She was Epstein’s right-hand woman for years, imagine what she knows?’
Prince Andrew’s name has been mentioned three times during the trial, including by one of Epstein’s pilots who confirmed he flew the Prince on the disgraced financier’s private jet dubbed ‘the Lolita Express’ because of the young girls it ferried around the world.
One of them, Virginia Roberts, claims she was forced to have sex with the Prince three times, including at Maxwell’s home in London. He vehemently denies all the allegations and insists he has never met Ms Roberts.