The US yesterday issued a blunt warning to Syria to stop Islamic militants crossing into Iraq, after US forces killed one of Saudi Arabia's most wanted terrorist suspects in the north-west of the country.

Speaking at a meeting of foreign ministers from the Group of Eight most industrialised nations in London, Condoleezza Rice, US secretary of state, said: "I would simply say to the Syrian government, let's not have more words about what they can do, let's have action. This is a government that can take action to stop border activity that contributes to the instability in Iraq."