The Edinburgh International Film Festival has come under increasing criticism for its decision to reject a donation from Israel.

Film director Gary Sinyor and the UK Jewish Film Festival have both attacked the EIFF for returning £300 given by the embassy in London to enable Israeli director Tali Shalom Ezer to attend the festival.

And one of Britain’s most distinguished producers, John Heyman, this week released a bitter letter he wrote to the festival’s chairman, Iain Smith, saying the festival’s actions had “endorsed bigotry”.

Mr Sinyor, whose film, Leon The Pig Farmer, won the festival’s award for best British film when it was premiered there in 1992, has asked the organisers to remove his name from its list of award winners. He has also called on the festival to issue a statement before it begins in June 17 to say it would take funding from Israel “as it would with any other country”.

Last month the EIFF returned the donation to bring Ms Ezer to Edinburgh, where her debut film, Surrogate, is due to be screened.

The festival organisers said they had acted after comments by the veteran film-maker Ken Loach, who claimed that Israel’s actions in Gaza made the donation “unacceptable” and called for a boycott of the event. Describing Mr Loach as speaking on behalf of “the film community”, the organisers returned the embassy’s money.

But Mr Sinyor, writing in The Independent at the weekend, said that if Mr Loach were speaking for the industry, “my phone never rang”.

This week, he revealed that festival director Ginnie Atkinson had denied in an email exchange that she had been pressurised by Mr Loach to send the money back.

“I said, if that is the case, you have to come out and say so publicly,” said Mr Sinyor. “She replied that to go public again would be pointless. That wasn’t good enough for me, so I asked for my name to be removed from the awards list.

“If the organisers are saying they won’t take money from the embassy because it might cause people to throw bricks through their windows, it’s understandable, though spineless.

“But if they are saying it’s a philosophical mistake, they have to justify it. It’s even more serious because they are taking money from many other countries and Israel doesn’t deserve to be singled out in this manner.

“My argument is not with Ken Loach but the EIFF, which has caved in to blackmail, and that is disgraceful. They are allowing Israel to be demonised under pressure from extremists.”

Judy Ironside, director of the UK Jewish Film Festival, said: “While we understand that this is a difficult situation, we feel that it is extremely regrettable that a public-funded festival should bow to boycotts made against it and that the EIFF should accept, at face value, the position taken by Ken Loach as the voice of the UK film community.

“We are questioning if this response has been made, either now or in the past, in respect of other countries whose films have been programmed. Contributing to the politicisation of what is otherwise an international cultural gathering is not a good principle.”

John Heyman, producer of films such as A Passage to India and The Go-Between, is also an agent whose clients have included Elizabeth Taylor, Richard Burton, Shirley Bassey and Burt Bacharach. His son, David, is the producer of the Harry Potter films.

Mr Heyman this week released the text of a letter he has written to EIFF chairman Iain Smith. He wrote: “I was appalled to read a recent statement that quotes the Edinburgh Film Festival as accepting that Ken Loach spoke on behalf of the film community in his repeated advocacy of a cultural boycott of the state of Israel.

“Well, as a member of the film community I want to refute that statement. He in no way represents either me or most of my colleagues. In every statement he makes on Israel, Mr Loach sounds like a broken gramophone repeating and repeating his negativity, while adding nothing new or constructive to the debate. He succeeds only in fuelling and refuelling the hatred and bigotry he espouses with such conviction...It is sad that a talented director, who clearly means so well, fails so miserably in the integrity of his advocacy.

“Over the years Mr Loach has convinced himself that he has the answers and therefore all those of us who do not agree with him not only don’t ‘know’, but are relegated, patronised and pitied for not finding The Way. I am sad that you and your festival would choose to issue a mis-leading statement based on a false assumption and therefore endorse and perpetuate bigotry.”

A spokesman for the EIFF said no further comment would be made.