David Cameron abandoned plans to arm the Syrian rebels after being warned by military chiefs that it could embroil British forces in an all-out war.
Senior military figures have warned the Prime Minister that with the momentum on the side of President Assad’s regime, sending small arms and missiles is unlikely to make a difference.
There are also growing concerns that arms sent to Syria could end up in the hands of extremists rather than moderate rebels, potentially presenting a long-term threat to British security.
More significant military intervention, such as introducing a no-fly zone over Syria, could mire Britain in a conflict for months because of the strength of the regime’s air defences.
The move represents a significant climb-down by Mr Cameron. He and his Foreign Secretary, William Hague, have been keen to act. In May he demanded an end to the EU arms embargo to give him more options.
His wife, Samantha, was reportedly pushing for him to take a more robust response after being moved by the scale of the humanitarian crisis in Syria.
She travelled to a refugee camp in her role as a charity envoy with Save the Children, where she met children who have been left traumatised by the conflict.
She said at the time: “As a mother, it is horrifying to hear the harrowing stories from the children I met today. No child should ever experience what they have. With every day that passes, more children and parents are being killed, more innocent childhoods are being smashed to pieces.”.
However, Mr Cameron has been told by Tory whips that there is little prospect of winning a vote on arming rebels in the Commons.
His decision has been swayed by the advice of military chiefs at the National Security Council, who raised concerns about the strength of the Syrian military.
A source close to Downing Street last night confirmed that Mr Cameron is not planning to arm Syrian rebels.
British forces will instead draw up plans to help train and advise moderate elements of the opposition forces fighting the regime.
John Kerry, the US Secretary of State is attempting to push rebels and the regime to the negotiating table.
However, British government sources have expressed frustration that they have little idea what he is seeking.
Ministers believe it could take 18 months before President Assad is forced to the negotiating table, although it could take significantly longer after the advance of the Syrian government forces.
Downing Street said: “No decision has been taken to supply arms to the opposition. The NSC continues to review the decision in Syria and to examine all the options closely”.