Jeremy Corbyn was heckled at a Stop the War coalition conference in central London on Saturday.
The Labour leader was yelled at by protesters as he arrived at the TUC’s Congress House, where he was due to give a speech.
A handful of campaigners launched a tirade as the famously anti-war politician took his seat alongside a panel on stage, the Press Association reports.
The group claimed they were angry at Corbyn’s failure to call for regime change in Syria.
Two women at the back initially started the volley of accusations, saying: “Jeremy Corbyn, where were you?” and “Your silence is complicit”.
Another man, Oz Katerji, 29, was standing closer to the stage and was escorted out of the building after shouting in Corbyn’s direction.
Their protests were soon drowned out by a chant of “no more war” from the hundreds of campaigners in attendance at the conference, who are thought to be among Corbyn’s core supporters.
When the Labour leader, who has been embroiled in fresh disputes within his party following a shadow cabinet reshuffle, eventually started his speech, he was again interrupted by one man, who called out: “What about Aleppo?”
Corbyn called for a “political solution” to the long-running conflict in Syria during his address to the room.
Speaking outside, Katerji said he had acted because Corbyn had “deliberately marginalised Syrian voices”.
He added: “Jeremy Corbyn himself will never say the words ‘Assad must go’, he will never say there needs to be a transition in Syria out of the Syrian government’s power - that is why we’re protesting.”