The head of Libya's opposition council says the rebel group's offer for leader Moammar Gadhafi to remain in the country if he cedes power has expired.

Mustafa Abdel Jalil said Wednesday that the proposal, which was presented to a United Nations envoy about a month ago, had a deadline attached.

Libyan Prime Minister Al-Baghdadi al-Mahmoudi has said Mr. Gadhafi's departure is not up for discussion.

The Libyan government has also condemned Britain's decision to recognize the opposition Transitional National Council and expel all of Libya's diplomats, calling the moves “illegal and irresponsible.”

British Foreign Secretary William Hague said Wednesday the decision is based on the opposition's increasing legitimacy, competency and success in reaching out to Libyans across the country.

Hague said the council is working toward a more open and democratic Libya, which he said is in “stark contrast” to Mr. Gadhafi, whose “brutality” against the Libyan people has stripped him of legitimacy.

The foreign secretary also said Britain will release $149 million in frozen Libyan assets to pay for fuel and basic needs in rebel-held territory.

The United States, France and more than 30 other countries have recognized the council as Libya's interim government.

Britain's announcement came a day after Libyan TV showed the man convicted of the 1988 bombing over Lockerbie, Scotland, at a pro-Gadhafi rally in Tripoli. Abdel Baset al-Megrahi returned to Libya after Scottish authorities released him from prison in 2009 because of health concerns.