The Labour leader vowed: “I’m not going anywhere” as the head of the Unite union Len McCluskey warned the party’s MPs against using the issue as an excuse to stage a coup.
The outcome of today’s shadow cabinet meeting could prove decisive after Defence Secretary Michael Fallon admitted yesterday the government does “not yet” have a House of Commons majority to approve RAF bombing of Islamic State (IS) in Syria.
However it is thought the government plans to bring a vote to MPs as early as this week.
Mr Fallon revealed he is now briefing supportive Labour MPs on the issue, with many poised to side with the government.
Deputy Labour leader Tom Watson is among those who are likely to back military action and will press at today’s meeting for a “free vote” for his party’s MPs. The SNP is poised to vote against military action.
Mr Corbyn, who is against airstrikes, has refused to commit to offering a free vote and delivered an impassioned critique yesterday of Prime Minister David Cameron’s case for attacking IS in its heartlands.
Asked whether Labour MPs – dozens of whom are thought to be considering supporting action – would be given a free vote, Mr Corbyn said: “No decision has been made on that yet, I am going to find out what MPs think.
“Obviously there are strong views on both directions. We will have a further discussion on this. We will make that decision not at this moment but later on.”
Mr Corbyn said he had received 70,000 responses to a survey sent out to Labour supporters on Friday canvassing their opinions and a decision would be taken “as a party”. The poll has been criticised as an attempt to use his grassroots powerbase to “bounce” the shadow cabinet into submitting.
He said: “My view about the membership of the Labour Party – they must have a voice.
“Labour MPs need to listen to that voice, they need to try and understand where people are coming from on this. We will come to a decision as a party.”
The veteran left-winger, who has been a serial rebel throughout his House of Commons career, said: “I understand dissent, I understand disagreement from leadership.”
But asked whether the whipping position would be a collective decision by the shadow cabinet, Mr Corbyn said: “It is the leader who decides. I will make up my mind in due course.”
Asked if there was any chance divisions in the party could force his resignation, Mr Corbyn said: “I’m not going anywhere. I am enjoying every moment of it.”
Mr McCluskey defended Mr Corbyn for canvassing party members.
He said: “He has been denounced for writing to MPs and party members making his views on Syria clear – as if his huge mandate, which included support for his long-standing anti-war record, had simply earned him the right to be seen but not heard.
“Yet at the same time members of the shadow cabinet are making their own pro-bombing views plain, either publicly or in off-the-record briefings.
“And backbench MPs are even calling on him to quit for having the temerity to maintain his values and principles, with one even comparing him disgracefully to a ‘fuhrer’. That is not open debate, it is abuse and should have no place in the party.
“The thought that some Labour MPs might be prepared to play intra-party politics over an issue such as this will sicken all decent people.”
He added: “Any attempt to force Labour’s leader out through a Westminster Palace-coup will be resisted all the way by Unite and, I believe, most party members and affiliated unions.”
Mr Fallon said he had been briefing Labour MPs on military action over the weekend but stressed the government does “not yet” have a guaranteed majority to back airstrikes.
The Defence Secretary rejected claims bombing Raqqa and other IS-held cities could lead to large numbers of civilian casualties as the terror group retreats into tunnels or uses local population as “human shields”.
He claimed the RAF’s precision airstrikes had not claimed a single civilian life during action taken against IS in Iraq and that Britain had “very strict rules of engagement”.
He warned that the UK’s reputation would be damaged and the population less safe if action was not taken in Syria.
Pressed on the nature of a 70,000-strong army of moderate Syrian forces in Syria referred to by Mr Cameron, Mr Fallon said: “We do know who they are and this is an independent joint intelligence committee assessment.
“It’s not ministers making this figure, it’s their assessment and it’s supported by academics.”
Shadow chancellor John McDonnell said Mr Corbyn would take a decision on which way to whip this morning and make a recommendation to the shadow cabinet meeting.
He said: “I want on these sort of issues an unwhipped vote, because they are above party politics.”
Shadow justice secretary Lord Falconer confirmed there were “significant differences” within the shadow cabinet. He added: “It is unlikely that we will be able to agree a yes or no answer.”
Deputy Labour leader Tom Watson said:“After the week that we’ve had, the best way of holding the party together, but allowing MPs to solemnly express what they feel, is for us to have a free vote.”