Updated

European nations are discussing whether to overturn an arms embargo on Syria and seeking to press Arab countries and the United States for a new impetus to end the deadly 20-month conflict, Britain's foreign policy chief said Friday.

British Foreign Secretary William Hague met in London with Mouaz al-Khatib, head of the new Syrian National Coalition for Opposition and Revolutionary Forces, but said that the U.K. would not yet join France in officially recognizing the opposition group as the representative of Syria's people.

Officials from the U.S., France, Germany, Qatar, Turkey and other nations were attending meetings in London with the new opposition group, aimed at determining how better to support opponents of Syrian President Bashar Assad and to stress the need for the opposition fighters to respect human rights.

"We cannot stand still, we cannot just say we will leave things as they are in Syria, because it is a gravely deteriorating situation," Hague told reporters. "How we respond has to be well judged, well thought through."

Though Britain has insisted so far that it will not supply weapons to Syria's rebels, Hague confirmed that its National Security Council had discussed whether a European Union arms embargo could be lifted. The issue is likely to be discussed at a meeting of European foreign ministers on Monday.

Since May 2011, the EU has imposed a ban on the export of weapons and equipment to Syria which could be used for "internal repression." In July, the 27-nation bloc asked members to stop and inspect any ships or aircraft bound for Syria that they suspect could be carrying arms.

France has already raised the possibility of sending "defensive weapons" to Syria's rebels -- though Russia, which has backed Assad's regime by vetoing action at the United Nations Security Council, has warned that such a move would violate international law.

"We must not militarize the conflict ... but it's obviously unacceptable that there are liberated zones and they're bombed" by Assad's regime, French Foreign Minister Laurent Fabius said Thursday in an interview with RTL radio.

However, a senior EU official said Thursday that if an arms embargo against Syria was restructured to allow arms to go to rebels but not to the regime, it would likely be very difficult to police. For that reason, the EU is unlikely to change the embargo, the official said. He spoke on condition of anonymity because of standing EU rules.

The U.N. Security Council hasn't imposed any arms embargo on Syria, amid Russia's and China's refusal to back tough measures against Assad.

In London, Hague insisted that Syria "needs a diplomatic and political solution -- a military victory of one side over the other would be a long, expensive process in terms of human life."

According to anti-government activists, Syria's civil war has seen more than 36,000 Syrians killed since March 2011, when an uprising began against Assad's regime. The fighting and flood of refugees seeking safety have also spilled over into several of Syria's neighbors, including Israel, Lebanon, Turkey and Jordan.

Suheir Atassi and Riad Seif, vice presidents of the Syrian National Coalition for Opposition and Revolutionary Forces, also attended Friday's meeting of Al-Khatib and Hague.

The three Syrians will travel to Paris on Saturday for talks with French President Francois Hollande.

"I hope this meeting today will mark a turning point for the Syrian people, that it will begin the major steps towards a political transition in Syria," Hague said.