Kurdish forces attacked Islamic State fighters near the Kurdish regional capital of Irbil in northern Iraq on Wednesday in a change of tactics supported by the Iraqi central government to try to break the Islamists' momentum.

The attack 40 km (25 miles) southwest of Irbil came after the Sunni militants inflicted a humiliating defeat on the Kurds on Sunday with a rapid advance through three towns, prompting Iraq's prime minister to order his air force to back Kurdish forces for the first time.

"We have changed our tactics from being defensive to being offensive. Now we are clashing with the Islamic State in Makhmur," said Jabbar Yawar, secretary-general of the ministry in charge of the Kurdish peshmerga fighters.