William Hague has described his "deep frustration" over the ongoing bloodshed in Syria.
The Foreign Secretary said sanctions against Syrian president Bashar Assad's regime were working, but he wanted quicker action to oust the leader.
Mr Hague was speaking after yesterday's international conference on Syria which accepted a peace plan for the country.
Officials estimate more than 15,000 people have died in Syria since pro-democracy campaigners took to the streets 16 months ago to demand reforms as the Arab Spring swept the Middle East and North Africa.
Mr Hague said: "Is it deeply frustrating that hundreds of people are dying every week while we talk? Of course it is."
But he hailed yesterday's summit on reinforcing calls for action.
"We made one step forward that's worth having, which is that we agreed with Russia and China what a transitional government should look like, that there should be a transitional unity government in Syria, that that should be made up of people from the present government and opposition groups on the basis of mutual consent, which would of course exclude president Assad from that," the Foreign Secretary told BBC1's Andrew Marr Show.
"That is a step forward from our point of view in Russia's position. Now we have to try and bring that about."
Mr Hague admitted the international world was "some way from resolving" the crisis, but added: "We are putting great energy into it."
Shadow foreign secretary Douglas Alexander believed yesterday's conference was "a diplomatic fudge".
He told Sky News' Murnaghan programme: "Even diplomats have struggled to paper over the cracks that were apparent in Geneva.
"The international community ... is deeply divided and that divide is dangerous when you have people dying."
Speaking after yesterday's conference in Geneva, United Nations special envoy Kofi Annan said: "It's for the Syrian people to determine the future of the country."
He added: "There must be a commitment to accountability and national reconciliation. It is for the people of Syria to come to a political agreement but time is running out.
"We need rapid steps to reach agreement. The conflict must be resolved through peaceful dialogue and negotiation alone.
"Conditions conducive to a political settlement must now be put in place. The bloodshed must end."