The British Government will push for a strong international response to reports of a massacre of civilians by Syrian forces.
United Nations observers say at least 32 children under the age of 10 and sixty adults were killed.
The Foreign Secretary said the UK will press for an urgent session of the United Nations to co-ordinate the response to the "appalling" crime. He said:
Mr Hague also called for:
- The Syrian regime to grant "full and immediate" access to Houla for UN monitors
- End all military options against civilians
The death toll is one of the highest for any single event since the popular uprising against Bashar Assad began in March 2011.
The head of the UN observer team in Syria confirmed at least 32 children under the age of 10 were killed in Friday's attacks north west of Homs. More than 60 adults were also killed. General Robert Mood condemned the attack, and said:
Video has emerged claiming to show a mass burial following reports of an attack by Syrian forces. These pictures have not been independently verified.
The killings are a serious set-back to an international peace plan brokered by envoy Kofi Annan meant to end the violence in Syria.
The basis of the plan is a cease-fire between President Bashar Assad's forces and Syrian rebels.
It was supposed to start on April 12 but has never really taken hold, with pockets of daily violence.