Feb. 25 (Bloomberg) -- Turkey refused to bow to pressure from the U.S. and the United Nations to wrap up a military operation in northern Iraq, as fighting between its soldiers and Kurdish militants entered a fifth day.

Turkey may take a decision on when to pull its troops out of the region ``in the coming days,'' government spokesman Cemil Cicek told reporters in Ankara, adding that the UN Charter allows Turkey to enter northern Iraq under articles governing self-defense.

The U.S. government and UN Secretary-General Ban Ki-Moon, concerned that the battles may further destabilize Iraq, have urged Turkey to end the military operation against members of the Kurdistan Workers' Party, or PKK, as soon as possible.

Turkey's military entered Iraq's Kurdish-controlled north on Feb. 21 and said yesterday that 112 PKK fighters and 15 Turkish soldiers had died in the fighting. The PKK has killed 81 Turkish soldiers, Bahoz Erdal, a leader of the group, told the Netherlands-based Firat news agency today.

Turkey has fought the PKK, branded a terrorist organization by the U.S. and the European Union, since 1984 at the cost of almost 40,000 lives. About 4,000 of the group's fighters have stationed themselves in northern Iraq since their leader Abdullah Ocalan was captured and put on trial by Turkey in 1999.

Turkish fighter jets pounded PKK positions overnight in and around Hakurk, about 20 kilometers (12 miles) from the Turkish border, as troops pressed on with the offensive, Agence France- Presse reported, citing unidentified security officials. Up to 10,000 soldiers are taking part in the operation, Turkish media have said.

The Turkish government should respect the international borders between Iraq and Turkey, Ban Ki-Moon said on Feb. 22. The U.S. hopes the operation will be short and avoid civilian casualties, Defense Secretary Robert Gates said Feb. 24.

Turkey is attacking civilian infrastructure located far from border areas where the fighting is taking place, Nechirvan Barzani, prime minister of the semi-autonomous regional administration governing northern Iraq, said late yesterday.

``This demonstrates that despite its stated aims, Turkey is targeting the Kurdistan region itself,'' he said in a statement on his administration's Web site. ``I am surprised by Baghdad's weak response to this clear violation of its sovereignty.''

Turkey opposes autonomy for Iraq's ethnic Kurds and has accused them of harboring PKK militants.

To contact the reporter on this story: Mark Bentley in Ankara at mbentley3@bloomberg.net.

Last Updated: February 25, 2008 10:28 EST