WASHINGTON – The US military on Monday withdrew its fighter jets from the international air campaign in Libya, officials said, after NATO asked Washington to keep up bombing raids for another 48 hours.

The United States had planned to halt combat missions and Tomahawk cruise missile launches at the weekend but accepted a NATO request to continue the operations for another 48 hours until Monday.

US combat sorties ended at 2200 GMT, with American warplanes on standby as NATO takes the lead, Pentagon spokesman Captain Darryn James said.

After that, "US aviation assets are expected to cease strike sorties and will remain on an alert status if NATO requests their support," James said in an email.

NATO had issued the request to extend US bombing raids after bad weather last week hampered combat flights, which military leaders said allowed Moamer Kadhafi's forces to advance.

Between 2200 GMT on Tuesday and 1000 GMT on Monday, US aircraft carried out at least two raids but launched no Tomahawk cruise missiles, James said.

A US Harrier jet "engaged military vehicles near" Sirte and a US A-10 Thunderbolt "engaged military vehicles near Brega," he said.

The A-10 aircraft, equipped with a powerful 30mm cannon and able to withstand direct hits from enemy fire, are designed to take out tanks and other ground targets.

US lawmakers have criticized President Barack Obama for scaling back the US military's role, saying NATO allies have no equivalent ground-attack aircraft to the A-10 "warthog."

As other NATO countries plan to step up combat flights to replace the American aircraft, the US contribution will be confined mainly to electronic jamming, mid-air refueling, surveillance and search and rescue efforts.