Jeremy Corbyn has caused anger after he failed to refer to Israel by name while addressing the Labour Friends of Israel group.
The new Labour leader was heckled as he ended his short speech at the LFI annual reception at the party conference in Brighton on Tuesday night.
The heckler was Michael Foster, a showbusiness agent who stood for the party at May’s general election in Cornwall.
Standing at the back of the packed audience, Mr Foster shouted: "Say the word Israel, say the word Israel".
Mr Corbyn, a long-standing critic of Israel, was warmly welcomed to the event when introduced by LFI chair Joan Ryan MP, with activists cheering his name.
Mr Corbyn told the reception: "I have taken an enormous interest in the affairs of the Middle East. I’ve been nine times and met many people – some I agree with, some I don’t. I have neutral opinions on many things.
“But it’s also about dialogue and how you bring about that long-term dialogue. That’s what I want to see.
Watch Jeremy Corbyn getting heckled at the LFI event:
The moment Jeremy Corbyn was heckled at the Labour Friends of Israel reception pic.twitter.com/1ggN8ChSQs
— Emily Ashton (@elashton) September 29, 2015
“The issue of recognition of Palestine is something that was very important in the last Parliament – it may well come up again.
“I know there are people in this room that think it was premature. There were some in this room who supported it. everybody recognises the only way forward is through peace, through negotiation, through dialogue and discussion and through recognition of the rights and needs and traditions of all of the peoples of the region. That surely has to be the right way forward.
“I hope we can promote and encourage that peace process and that dialogue. I hope that means the siege of Gaza, or the restrictions on Gaza, can be lifted. I hope we can make progress that way.”
He thanked members of Britain's Jewish community for their efforts to help refugees fleeing violence in the Middle East.
"I want to say thank you to the Jewish community here who have opened their hearts and their doors and helped people that are desperate, seeking refuge and seeking a place of rescue," he said.
Mr Corbyn also railed against the threat of the far-right.
At Tuesday's event Shadow Foreign Secretary Hilary Benn called on both Israel and the Palestinians to work together to avoid further conflict.
He said: "The relationship, the enduring friendship between our two countries, our two peoples and our two parties is one that will endure during the weeks and the months ahead and one to which I am very strongly committed.
“I want to say a big thank you to the Labour Friends of Israel for the great work that you do.
“There is a great deal of passion and we have seen some of that displayed this evening, and I understand that. There is passion on both sides in this unresolved conflict.
“The goal all of us must work towards is to turn that passion into passion for a peace process and not into conflict and into war.”
Israel's Deputy Ambassador to Britain Eitan Na'eh told the reception: "I call on all true friends of Israel and the Palestinians to help bring about direct negotiations, as the best and indeed the only way to achieve peace - in good faith.
"I call from here to all true friends of Israel and the Palestinians to not just criticise Israel as friends sometimes do, but to be as vocal, as public and as true to your values in criticising the Palestinians when necessary reminding them of their responsibilities.
"I am thankful to the Labour Party for the support it has shown for the state of Israel over the years."
The Jewish Leadership Council said the new leader's attendance at the event was "a welcome step".
Zionist Federation director Arieh Miller said the event had offered Mr Corbyn "the perfect opportunity to start re-building a relationship that has come under immense strain".
"That he could go through the entire talk without even mentioning the word ‘Israel’ gives some indication of his apparent lack of interest in genuine engagement with both sides of the debate.
"It seems we now have a Labour leader who appears more comfortable meeting Hamas and Hezbollah than Israel-supporting party members."
A Board of Deputies spokesperson said: “Jeremy Corbyn’s failure to mention Israel by name at the event does seem bizarre and it does raise concerns.
"However, there is the possibility it might just have been a genuine oversight. It is certainly one of the matters we will be raising when we meet him.”