NATO agreed Wednesday to extend its air-and-sea campaign in Libya for up to 90 days as the country’s new rulers try to dislodge well-armed Moammar Gaddafi loyalists who are holding out in several towns.

The agreement to extend the U.N.-mandated mission to protect civilians, of which NATO took full command on March 31, came at a meeting of ambassadors of the 28 NATO states in Brussels.

ut NATO’s secretary general said the campaign could end sooner. “We are determined to continue our mission for as long as necessary, but ready to terminate the operation as soon as possible,” Anders Fogh Rasmussen said in a statement.

“While the technical rollover is for up to 90 days, the review will allow us to end our tasks at any time,” he added.