* Government forces seize oil town Brega, gain initiative
* G8 foreign ministers to discuss Libya
(Adds details from statement)
PARIS, March 13 (Reuters) - France promised on Sunday to step up efforts to persuade its partners to impose a no-fly zone on Libya after the plan won the backing of the Arab League.
League Secretary General Amr Moussa said the group had officially asked the U.N. Security Council to impose such a zone "against any military action against the Libyan people".
Arab support satisfies one of three conditions NATO set on n Friday for it to take on the task of policing Libyan air space, as requested by the rebels challenging Muammar Gaddafi's four-decade rule of the oil-producing North African country.
The League's call showed the international community wanted "to assure the protection of the civilian population in Libya and the respect of international humanitarian rights in the face of the terrible violence suffered by the Libyan population," French Foreign Minister Alain Juppe said in a statement.
"In order to complete these objectives, France will accelerate its efforts in the coming hours in consultation with its partners in the European Union, the Arab League, the U.N. Security Council and the transitional Libyan National Council."
Libyan leader Muammar Gaddafi's forces appear to have regained the momentum in a three-week-old conflict against the uprising inspired by popular revolts in Tunisia and Egypt.
Government troops seized the strategic Libyan oil town of Brega on Sunday, forcing rebels to retreat under a heavy bombardment and limiting their access to fuel.
France has been playing a leading role in the international response to the uprising, especially in its calls with Britain to secure U.N. support for a no-fly zone resolution.
Juppe said the Group of Eight foreign ministers would discuss Libya at a meeting starting in Paris on Monday. (Reporting by James Regan, editing by Tim Pearce)