Forces loyal to Libya's United Nations-brokered government are advancing cautiously on the remaining pockets of Islamic State group fighters holding out in the coastal city of Sirte.

The Tuesday push comes after months of intense fighting in Sirte between government forces and IS fighters, who gained a foothold in the country following the 2011 overthrow and killing of longtime dictator Moammar Gadhafi.

Pro-government fighter Mohamed Abdulla says the troops are "making progress every day," but needed better care for their wounded.

The United States has been supporting the fight against IS with airstrikes.

Efforts to unite the deeply divided country were dealt a major blow last August when the country's parliament, based in the eastern city of Tobruk, rejected the Tripoli-based government following a no confidence vote.