Iran warns US not to cross ‘red line’ on Syria

Iran has warned the US not to cross the 'red line' on Syria saying it would have "sever consequences", Fars news agency has reported.

"America knows the limitation of the red line of the Syrian front and any crossing of Syria's red line will have severe consequences for the White House," said Masoud Jazayeri, the deputy chief of staff of Iran's armed forces reacting to statements made by Western officials regarding the possibility of military intervention in Syria.

Jazayeri's statement comes as Iran continued to show its support for the regime of Syrian President Bashar al Assad. It also follows statements by UK Prime Minister David Cameron and US President Barack Obama saying they were "gravely concerned" about signs that an alleged chemical weapons attack took place in Syria.

The two leaders spoke with Canadian Prime Minister Stephen Harper by telephone last night as calls increased for UN investigators - who are already in the country - to be allowed access to the site of the alleged attack.

US Defence Secretary Chuck Hagel said the American military is ready to exercise "options" on Syria should force be called for, but he declined to say what that action might be according to Sky News.

He is under mounting pressure to act over the alleged use of chemical weapons, which humanitarian organisation Doctors Without Borders said had killed 355 people due to "neurotoxic" symptoms.

The group says it has treated more than 3,500 people showing symptoms of exposure to a "neurotoxic" agent. Rebel groups have claimed the attack was carried out by Assad's forces and that more than 1,000 people had died. The Syrian regime has denied the allegations.