The National Union of Students has rejected a call to condemn militant group Isis on the grounds that the motion was “islamophobic”, in a move which has promoted campaigners to accuse the body of being in the “stranglehold” of divisive “identity politics”.

The political split in the student body over the conflict in the Middle East erupted after a motion was put forward last month to the NUS National Executive Council, asking students to express “solidarity” with the Kurds in Iraq and Syria who are engaged in a bloody struggle against ISIS militants.

The motion, proposed by Daniel Cooper and Clifford Fleming with international students officer Shreya Paudel, called on British students “to condemn the IS and support Kurdish forces fighting against it, while expressing no confidence or trust in the US military intervention.”

However the call, which also called for unity among Muslims and has already been passed by the Scottish NUS, was rejected by a members led by black students’ officer Malia Bouattia, according the student website The Tab.

Ms Bouattia is reported to have spoken against the motion. She is reported to have said: “We recognise that condemnation of Isis appears to have become a justification for war and blatant islamophobia. This rhetoric exacerbates the issue at hand and in essence is a further attack on those we aim to defend.”

Ms Bouatti’s opposition to the motion was supported by fellow NEC member Aaron Kiely. On his blog he wrote: “The Stop the War Coalition and CND are being falsely accused of backing Isis. Now student activists are similarly being attacked. The NUS black students’ officer and others who are standing up against this new war should be supported and the maligning of the anti-war movement opposed.”

However Mr Cooper, one of the motion’s sponsors, hit out at the student body’s divisions. On his blog he wrote: “The motion then fell as large numbers of NEC members either abstained or voted against (including the bulk of the political left on NEC). I think this says a lot about the current state of the student movement.” He added: “There is a stranglehold of 'identity politics' on the student movement… essentially the idea is widespread that if a liberation officer opposes something, it must be bad.”

However in a sign that even the proponents of the motion are wavering on the issue, Mr Fleming, the national co-chair of the Young Green Party and an NEC member, told The Independent that the bill, which he co-proposed, failed to pass as it could encourage intervention.

He said: “It was voted down due to a general feeling that the motion currently could lead to pro-interventionism – which nobody wanted.”

Despite proposing the motion with Mr Cooper, he said: “I find it completely inappropriate how it was claimed that identity politics has a stranglehold on the NEC. Of course identity politics has a big voice on the NUS NEC; it is for those who self-define and lead campaigns to voice who they represent.”

A spokesperson for the NUS said: “At our most recent NEC meeting, a motion on this issue was presented and voted on by all members. Some committee members felt that the wording of the motion being presented would unfairly demonise all Muslims rather than solely the group of people it set out to rightfully condemn.