The US launched air strikes against Isis in the Libyan city of Sirte in a bid to support forces allied to the government who are battling to regain control of the jihadi group’s stronghold in the north African country. The Pentagon said that Monday’s “precision air strikes” on Isis targets in Sirte were the first of a wave aimed at helping the Libyan forces “make a decisive, strategic advance” on the port city. The US strikes were the first in Libya since February. They were authorised by President Barack Obama following a recommendation from Ash Carter, defence secretary, and General Joseph Dunford, chairman of the joint chiefs of staff, the Pentagon said. Isis seized control of Sirte, the home of former strongman Muammer Gaddafi, last year and the city has become a critical battleground in the fight against the militant group.