Iraq's prime minister claims his country's intelligence officials have uncovered a plot to attack underground rail systems in the US and Paris.

Prime Minister Haider al-Abadi said he was told foreign fighters among the Islamic State group in Iraq were plotting an "imminent" attack on subways in Paris and the U.S.

Speaking on the sidelines of the United Nations General Assembly, he told reporters that the details he had received looked credible.

He said the US had been alerted.

Meanwhile the British Prime Minister has chaired a cabinet meeting to discuss his commitment to join airstrikes against Islamic State militants in Iraq.

The motion to be debated by MPs in tomorrow's debate condemns the barbaric acts of IS against the peoples of Iraq - and it recognises the threat the group poses to wider international security.

But it does not endorse UK air strikes in Syria as part of the campaign.