Russia and Iran warn Trump they will retaliate militarily against the US if it crosses their 'red line' again with attacks on Assad in Syria

Russian and Iranian forces last night warned Donald Trump (left at the White House, yesterday) they would retaliate with military action if he launched more airstrikes on Syria. In an ominous threat raising the prospect of war, they said the US President had crossed a 'red line' with his surprise missile bombardment (top right) on Bashar al-Assad's forces. 'From now on we will respond with force to any breach of red lines and America knows our ability to respond well,' the military chiefs said in a joint statement with Hezbollah. The Russian Embassy in London last night suggested there could be 'real war' if Moscow is presented with an ultimatum over Syria. Pictured: Vladimir Putin meets with Iranian president Hassan Rouhani (right in the main picture with the Russian president) in Moscow in March and crew members at the recent launch of the Kazan, a Project 885M Yasen-class nuclear-powered multipurpose attack submarine, at the Sevmash shipyard in northern Russia (bottom right).