Berlusconi's office said in a statement that Italy had decided to beef up its military action in Libya to better contribute to protecting civilians.
Italy had previously said it would not participate in airstrikes against Libyan targets, given its 40-year colonial rule over the country, but in Monday's statement it said it had decided to increase its "operational flexibility."
The statement stressed that Italian airstrikes would only be against "specific military objectives."
Italian aircraft and navy ships had previously only been involved in Nato's Libya mission for refueling and other operations.
Rebels have complained that NATO-led firepower hasn't been sufficient to help them advance against Moammar Gadhafi's forces.