Cameron says Russian military action in Syria a 'terrible mistake'

Britain's Prime Minister David Cameron prepares to greet President Nicos Anastasiades of Cyprus at Number 10 Downing Street in London, Britain September 18, 2015. REUTERS/Peter Nicholls

MANCHESTER, England (Reuters) - British Prime Minister David Cameron said on Sunday that Kremlin chief Vladimir Putin's decision to take military action in Syria to support Syrian President Bashar al-Assad was a "terrible mistake".

Russia has begun striking targets in Syria - a dramatic escalation of foreign involvement in the civil war which has been criticised by some as an attempt to prop up Assad, rather than its purported aim of attacking Islamic State militants.