The European Union backed on Monday an Arab League call for a UN peacekeeping mission in Syria and urged the UN Security Council to act in order to stop the violence there.

As Syrian troops pounded the protest hub of Homs again on Monday, Britain called for urgent international talks on the Arab League proposal but cautioned that Western nations are unlikely to contribute to the force.

"We welcome these bold decisions and the strong and clear commitment and leadership that the Arab League is taking to resolve the crisis in Syria," said Michael Mann, spokesman for EU foreign policy chief Catherine Ashton.

"The EU's first goal is an immediate cessation of killings and therefore we are very supportive of any initiative that can help achieve this objective, including a stronger Arab presence on the ground in cooperation with the UN to achieve a ceasefire and the end of violence," he said in a statement.

"We are constantly in contact with the secretary generals of the Arab League and the UN in order to discuss how this can be set in motion as soon as possible," Mann added.

The 22-nation Arab League agreed Sunday to open contacts with Syria's opposition and ask the United Nations to form a joint peacekeeping force to the nation.

The proposal came a week after Russia and China vetoed a UN Security Council resolution, backed by Arab and European states, aimed at ending 11 months of bloodshed in Syria.

"The Arab League has made again a strong appeal to the UN Security Council," Mann said. "We renew our urgent calls on all members of the Security Council to be constructive and act with responsibility at this crucial moment."

Germany called on the Security Council to examine the Arab League proposal "as quickly as possible."

Russian Foreign Minister Sergei Lavrov said Moscow wanted "clarifications of certain points" in the Arab League initiative and stressed that a ceasefire was needed in Syria before the UN could deploy peacekeepers.

British Foreign Secretary William Hague also said the success of a peacekeeping mission depended on a "credible ceasefire" being established and an end to President Bashar al-Assad's crackdown on civilians.

At its meeting in Cairo, the Arab League also endorsed an international "Friends of Syria" group, which will meet in Tunisia next week.

"We will discuss urgently with them the proposals for a joint Arab League-United Nations peacekeeping force," Hague said, adding that the West was unlikely to participate in the mission.

"I don't see the way forward in Syria as being Western boots on the ground, in any form, including in peacekeeping form," he told a news conference during a visit to South Africa.

"But of course if such a concept could be made viable we will be supporting it in all the usual ways."

Italian Foreign Minister Giulio Terzi called for a "large" international consensus on the peacekeeping mission. He also welcomed the Arab League's decision to open contacts with Syria's opposition.

"Encouraging the links between, and the unification of, the various elements is an absolute priority in order for a Syrian political process backed with the support of the international community to begin," Terzi said.

Mann said the EU is also "in close contact with all opposition groups which respect human rights and want an inclusive, democratic transition."

The EU plans to adopt a new round of sanctions against Assad's regime on February 27 and the bloc will also play a "very active part" in the Friends of Syria, he said.

Ashton will meet with US Secretary of State Hillary Clinton in Washington later this week and will take part in the "Friends of Syria" meeting on February 24 in Tunisia.