The Foreign Secretary says he agrees with America's conclusion that Syrian government forces have used chemical weapons.
But William Hague's stopped short of backing the US decision to arm rebel fighters who are trying to overthrow the Assad regime. Mr Hague says the international response will be discussed at the G8 summit in County Fermanagh next week.
Meanwhile, a priest ministering to people in one of the areas worst affected by the conflict has spoken of his desperate struggle to provide basic food, shelter and medicine to more than 30,000 people fleeing the violence.
The priest, who cannot be named for security reasons, sent a report to Catholic charity, Aid to the Church in Need.
In it he gives an account of the "many explosions" of the past week in Homs, one of which took place very near to his church which killed 11 people, including five of his parishioners.
He also pays tribute to a Jesuit priest and 74 other Christians living in a "siege-like manner" in Homs' ancient Old City, where many historic churches lie in ruins after fierce fighting. Facing a shortage of food and medicine, he said the Jesuit and his flock rely on aid parcels being sent to them.
The priest writes that people continue to cling to hope in spite of the difficulties. He said:
"We have a great hope.
"Churches still ring bells for prayers and all people come and share Mass. Nobody can steal our hope and joyfulness."