By Suzannah Hills PUBLISHED: 05:33 EST, 16 June 2013 | UPDATED: 01:51 EST, 17 June 2013 Iran is preparing to send 4,000 troops in to Syria to support Syrian President Bashar al-Assad in the wake of America's announcement it will be providing 'military aid' to the country's Muslim rebels. President Barack Obama made the pledge earlier this week after the U.S. claimed it found 'conclusive evidence' Assad's regime has used chemical weapons against the rebel forces - which includes the most extreme Sunni Islamists - and has called for Britain and France to back the move. While Britain hasn't made a guarantee either way as yet, more than 350 Royal Marines are being sent to Jordan as part of an 8,000-strong 'multinational exercise', further increasing tensions in the war-torn region.
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350 Royal Marines on way to Jordan as part of 'multinational exercise'
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David Cameron welcomed Barack Obama's vow to provide 'military aid' to Syrian rebels but has so far only promised Britain's 'non-lethal' support
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Britain and U.S. to tackle Putin for supporting Syria's president at G8 meet
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Videos on YouTube shows rebels with shoulder-fired heat-seeking missiles
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Clips prompt fears arming rebels will put weapons in hands of extremists
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