Libyan security officials say warplanes have again bombed a military air base that until a day earlier was Tripoli's only functioning airport, shortly after the Islamist-backed prime minister said his government was at war.

Late Monday, Prime Minister Omar al-Hassi said the Cabinet will now adopt "a policy of confrontation and war," comments directed at his rivals in Libya's internationally recognized government based in the country's east.

The Monday-Tuesday bombings of Matiga air base — held by Islamist-allied militias — appear to be part of efforts by the elected government to retake the capital after the Islamist-allied militias seized it.

The base had been used for civilian purposes since last summer when Tripoli International Airport was destroyed. Officials spoke on condition of anonymity as they weren't authorized to brief reporters.