Syria: Take Action Or Risk Disaster - Blair

Tony Blair has insisted the West must intervene against the Syrian government to prevent "catastrophic consequences".

The former Prime Minister urged Britain to help the US arm opposition forces fighting President Bashar al Assad and his regime.

Mr Blair expressed fears that both sides will begin to use chemical weapons as an "acceptable form of warfare" if no action is taken.

His warning came after the US said the Assad regime had crossed a "red line" by using nerve gas and David Cameron promised Syria would top the agenda at the G8.

"I feel very strongly that we are in danger of a failure with catastrophic consequences," Mr Blair told The Times.

"This is no longer a civil war between factions within Syria. We should be taking a more interventionist line.

"You don't have to send in troops, but the international community should think about installing no-fly zones."

The peace envoy added that the use of chemical weapons and intervention of Hezbollah, at the instigation of Iran, has "completely changed the game".

The US has vowed to take action in Syria after obtaining what it believes is proof the government used chemical weapons to kill up to 150 rebels.

Syria's Foreign Ministry has accused the US of lying to give it an "excuse" to intervene in the civil war, which has now raged for more than two years.

But the Obama administration has promised to provide "direct military support" to the opposition, and is also considering a no-fly zone as it looks at various options for intervention.

This could mean destroying Syria's sophisticated Russian-built air defences, which would thrust it into action of the sort taken by Nato in Libya to topple Colonel Gaddafi.

But Moscow could prove a roadblock. The Kremlin has already dismissed US evidence about nerve gas and could use its veto in the UN Security Council.

Russia has already voted three times to stop resolutions that could be used to threaten force against Mr Assad.

Mr Cameron discussed the conflict with leaders including Barack Obama, Francois Hollande, Angela Merkel and Enrico Letta of Italy in an hour-long video conference on Friday night.

He backed Washington's view that the regime had used chemical weapons, saying there was credible evidence of "multiple attacks".

The Prime Minister described Mr Assad as a "brutal dictator who is using chemical weapons under our nose" but insisted again that no decision had been made on the UK arming rebels.

He also disclosed attempts had been made by al Qaeda-linked elements to secure the weapons, which will raise concerns about any moves by the West to supply arms.

Mr Cameron is due to meet Russian leader Vladimir Putin in Downing Street on Sunday for talks ahead of the G8, with Syria sure to feature high on the agenda.

Its civil war grew out of protests that swept the Arab world in 2011 and has become by far the deadliest of the uprisings, with latest figures putting the dead at 93,000.

Western countries have repeatedly urged Mr Assad to leave power but declined to use the force deployed in Libya.

Syria is a much stronger country that straddles sectarian divides at the heart of the Middle East and is also backed by Iran and Russia, making any action hugely complicated.

US officials say Mr Obama will try to persuade Mr Putin to abandon support for Mr Assad when the two leaders meet in Northern Ireland next week.

Washington and Moscow are both calling for a peace conference in Geneva but prospects for the talks being held on time next month now seem dubious.