"When they start action, we also do... They carry out operations from the Iranian side of the border and we do so from the Turkish side," land forces commander Ilker Basbug said, the CNN Turk news channel reported on its web site.

The general said no such coordinated action had taken place in the past two months, but that it could be launched again in the future.

Separatist Kurdish militants of both Turkish and Iranian origin take refuge in the mountains of northern Iraq, where the frontiers of the three countries meet, and use camps there as a launching pad for attacks into Turkey and Iran.

"We are working in coordination with Iran in the region... We are sharing information," Basbug said.

Turkish and Iranian forces often shell rebel positions across the border.

Since December, Turkey has also carried out several bombing raids in northern Iraq and in February conducted a week-long ground offensive against camps of the separatist Kurdistan Workers' Party (PKK) there.

The PKK, which has waged a bloody campaign for Kurdish self-rule in southeast Turkey, is closely associated with Iran's Party of Free Life of Kurdistan (PJAK), which has recently stepped up attacks on the Iranian security forces.

Turkey and Iran have been helping each other on security matters, primarily to stop the movement of rebels across their porous border, since they signed a cooperation agreement in the late 1990s.

Turkish media have reported that the two neighbours hammered out a fresh deal in April involving intelligence sharing.

Following an air raid against PKK camps in northern Iraq in May, the Turkish army said senior rebel commander Cemil Bayik fled into a neighbouring country together with a large group of militants, engaging in clashes with local security forces.

The army did not name the country, but it is believed to be Iran. It said that its security forces killed many of Bayik's bodyguards, with the commander's fate unknown.

Listed as a terrorist group by Turkey and much of the international community, the PKK has been fighting for self-rule in Turkey's mainly Kurdish southeast since 1984. The conflict has claimed more than 37,000 lives.