Thousands of protesters have gathered outside Downing Street to urge MPs to vote against airstrikes on Islamic State targets in Syria.
They were joined by actor Mark Rylance, former MP George Galloway and musician Brian Eno, who all addressed the crowds.
The event was organised by Stop the War Coalition as David Cameron gave his strongest hint yet that he will call a vote on airstrikes despite opposition from Labour leader Jeremy Corbyn.
Rylance said he feared bombing in Syria would make the extremist group stronger:
You can't just write these people off as psychopaths and sociopaths. Some of them may be but some of them are just very, very angry, determined people.
The shadow international development secretary Diane Abbott told protesters the Prime Minister had been contacting Labour MPs to persuade them to vote for the air strikes.
At this point, I do not believe that bombing Syria will make it safe, any more than bombing Iraq made Iraq safe, bombing Afghanistan made Afghanistan safe and bombing Libya made Libya safe.
Meanwhile Mr Eno said joining air strikes on IS in Syria would "make all their dreams come true".
The Labour shadow cabinet is divided over the issue - some reacting furiously to a letter sent by Corbyn saying he would not support any bombing.
But a series shadow foreign secretary Hilary Benn and deputy leader Tom Watson, have said they would back air strikes.