Britain is planning to join forces with America and prepare its Royal Navy vessels against Syria, The Daily Telegraph is reporting.
Government sources said talks between the Prime Minister and international leaders, including Barack Obama, would continue, but that any military action that was agreed could begin within the next week.
The possibility of such intervention will provoke demands for Parliament to be recalled this week.
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After Roy Hodgson's resignation following England's humiliating exit from Euro 2016, who are the leading contenders to replace him?
The beleaguered Labour Party leader is clinging onto power in the face of as many as 150 MPs voting to remove him from the top job today.
Mr Osborne said he is "not the person to provide the unity my party needs".