A Labour MP wants the Government to come clean over David Cameron's contention Syria boasts 70,000 “moderate” ground troops - a centrepiece of his case for war.
Downing Street attempted to swat away Labour MP Louise Haigh's suggestion 30,000 of the 70,000 were "radical Islamists" as a "mischaracterisation", but she has told The Huffington Post tonight ministers still "need to be clear".
The shadow minister's concern followed a briefing of MPs from the national security adviser Mark Lyall Grant, underscored by the Deputy Chief of Defence Staff, Lt Gen Gordon Messenger, admitting the 70,000 was not a "coherent force" and represented a "spectrum of extremism".
She told HuffPost UK the meeting was a Government briefing - not a security one - attended by MPs and staff.
The MP, who has signalled she will vote against extending military action, said the Ministry of Defence "confirmed that the make-up of the 70,000 ground troops is of 40,000 ‘moderates’ and 30,000 ‘less moderates that are open to political debate’".
She went on: "The Government needs to be clear on exact make-up of the 70,000 figure, which forms key aspect of case for military intervention ahead of the vote."
Earlier today, Defence Secretary Michael Fallon backed the 70,000 troops figure - saying there was 20,000 in the north, 20,000 in the south and "groups" totalling 30,000. But he could not say if there was a Lawrence of Arabia-style figure to unite the clans.
Michael Fallon, second from left, and Lt Gen Gordon Messenger, second from right, were questioned about the 70,000 figure
Mr Cameron’s pledge that Britain will put no “boots on the ground” in Syria, and limit British action to RAF bombing raids, means relying on fighters already taking on ISIL.
In the Commons last week when making the case for war, the Prime Minister said the 70,000 figure was the “considered opinion” of the independent Joint Intelligence Committee - but immediately faced scepticsm.
Julian Lewis, chairman of the Defence Select Committee, said the large number of "non-Islamist, moderate, credible ground forces" was "a revelation to me".
Former Conservative minister Peter Lilley said he needed convincing that a Free Syrian Army "actually exist", rather than a "rag-tag group of clans and tribal forces with no coherent force".
Labour leader Jeremy Corbyn claimed today the 70,000 number was "mythical".
MPs were being briefed ahead of tomorrow’s crunch vote in the House of Commons. Ms Haigh was criticised by even a Labour colleague in Parliament after making the claim on Twitter, suggesting she had misrepresented the meeting.
Ms Haigh, Labour MP for Sheffield Heeley, wrote: “National Security Adviser confirms number of moderates on ground in Syria is 40,000 rest are much more radical Islamists.”
Conservative MP Gavin Barwell responded that was is “NOT what he said”.
And Stephen Doughty, a Labour MP, said there was “dismay in room from all sides” when her tweet began to make waves.
Appearing before MPs on the Defence Select Committee, Mr Fallon said he was "surprised people should be surprised that it was 70,000 in a country of 20 million fighting a civil war".
He added the figure relates to forces who can "play a part in supporting a different kind of government in Syria" and "take the fight to ISIL".
"That is what we mean by a moderate opposition force in Syria," he said.
“Those 70,000 are not all in one place, they're not a New Model Army drilled outside the walls of Raqqa (where ISIL HQ is based) - they are spread through Syria.
"Over 20,000 of the Free Syrian Army mainly in the north, around 20,000 in the southern front commanded by al-Zoubi, and groups to add throughout Syria to give you the 70,000."
But he added: “Is there a single commander who can wield all this together as Lawrence of Arabia tried to do 100 years ago? That I'm not sure of."
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Sat alongside him, Lt Gen Gordon Messenger, admitted: "This isn't a coherent force.
"There is a spectrum of extremism. Those that are inside the 70,000 are those that are 'moderate' and the next band - those we are prepared to accept might be part of a political process that is representative of the people they represent."
Asked if Ms Haigh was right to say Mr Lyall Grant had suggested 30,000 of the 70,000 were "radical Islamists", the Prime Minister's official spokeswoman said: “I think it’s a mischaracterisation.
"We make this assessment of 70,000 based on a complex picture in Syria of multiple groups…focused around two things: ideologically these groups are committed to a pluralist Syria and second a rejection of terror tactics.
"Within that there are some who are more engaged with the international community on the political process.”
Pressed again on Ms Haigh's precise description that the National Security Adviser had talked of 30,000 'radical Islamists open to political activity', the spokeswoman said she had talked to him and he'd disputed the claim.
"I would say that's a misrepresentation of that discussion. I would suggest that’s not what he said. There is a range of views within that. Clearly there are multiple groups."