Europe stepped up pressure on Syria on Tuesday as several nations recalled their ambassadors from Damascus and the EU considered new sanctions to cut the regime's access to cash.

France, Italy, Spain and the Netherlands decided to bring back their envoys for consultations, joining Britain and Belgium to protest the regime's relentless opposition crackdown. The United States has closed its embassy.

Paris denounced the "worsening repression" while Rome voiced the "firm condemnation and disgust of the Italian government for the unacceptable violence perpetrated by the regime in Damascus against the civilian population".

Gulf states also decided to withdraw their envoys, while Turkish Prime Minister Recep Tayyip Erdogan said Ankara would launch a new initiative "with those countries who stand by the Syrian people, not the regime".

Erdogan denounced Russia and China's torpedoing of a UN resolution backed by the West and the Arab League as a "fiasco for the civilised world" which had handed Syrian President Bashar al-Assad a "licence to kill".

"We cannot remain silent on what is happening in Syria and we cannot turn our backs on the Syrian people," Erdogan said as regime tanks pounded the central city of Homs for a fourth straight day.

During a visit to Brussels, Turkey's European affairs minister Egemen Bagis called on the international community to work together to put "an end to this massacre" and convince the regime to implement reforms.

The latest moves came as Russian Foreign Minister Sergei Lavrov said after talks with Assad in Damascus that the Syrian leader was "fully committed" to ending the bloodshed.

French foreign ministry spokesman Bernard Valero said Lavrov should use Russia's influence to make Damascus "understand its isolation" and support an Arab League plan aimed at ending the violence.

The 27-member EU began discussing new measures against Syria's central bank and a ban on gold and gems after China and Russia vetoed a UN Security Council resolution backing the League plan at the weekend.

"There's a long way to go yet, but we're looking at economic measures which will tighten further the Syrian regime's access to sources of finance," a European diplomat said.

Another diplomat said the sanctions could target Syrian central bank transactions as well as a ban on the sale of gold and other precious metals -- similar to measures taken against Iran last month.

The EU has already prohibited the delivery of bank notes and coins to the Syrian central bank in a previous set of sanctions approved last year.

A ban on gold and gems had been agreed in principle last year but a final decision was never taken. Diplomats said it was put back on the table this week.

The EU has imposed an asset freeze and visa ban on 108 individuals and an asset freeze on 38 entities. A diplomat said more asset freezes were being discussed.

The bloc is also enforcing an arms embargo and a ban on imports of Syrian crude oil.

The EU's External Action Service, however, has no plans to withdraw its head of delegation in Syria, arguing that it needs to have people on the ground to "report and observe what is going on" since there is no free press in Syria.

Michael Mann, an EU spokesman, said the bloc's foreign service will continue "to do everything we can diplomatically" with the 27 EU states and international partners "to try and bring an end to this totally unacceptable situation."

The spokesman for foreign affairs chief Catherine Ashton said the EU continues to support Arab League efforts to end the 11-month-old crackdown, which rights groups say has claimed the lives of about 6,000 people.

"We think that this should be an Arab-led process," Mann said. "We call upon the international community to take its responsibilities and to have an international solution to this problem."

Speaking on a visit to Lisbon, Morocco's Foreign Minister Saad-Dine El Othmani called for "every possible pressure to stop the violence" short of a military intervention.

He added that it was up to China and Russia to step up the pressure on Syria.