Oct. 23 (Bloomberg) -- The Turkish army, NATO's second- largest, is poised for a possible attack on northern Iraq that may begin with air strikes and strafing runs by helicopter gunships aimed at smashing the mountain hideouts used by Kurdish guerrillas.

Turkey might follow the strikes with tanks and armored personnel carriers that would punch across the border as helicopters ferry commandos to a string of guerrilla bases some 20 kilometers (12 miles) from the frontier, military analysts say. The Turks would face rebels who have had years to reinforce their bases and are well-trained in mountain warfare.

``It would be a major incursion,'' said Michael Radu, co- chairman of the Center on Terrorism at the Foreign Policy Research Institute in Philadelphia. The Turks ``cannot pull back now and say, `We have made all these noises and we increased oil prices and OK, we'll send 200 people in.' That is not going to happen.''

The preparations continued amid a day of furious diplomacy aimed at forestalling the attack, which threatens to disrupt the North Atlantic Treaty Organization, U.S. policy in Iraq and its relations with one of its most important allies in the Muslim world.

``The Iraqi government should know that we can use the power vested in us to conduct a cross-border operation at any time,'' Prime Minister Recep Tayyip Erdogan said at a news conference with U.K. Prime Minister Gordon Brown in London today. The U.S. should know that ``the time has come'' for it to resolve the dispute.

`Various Ways'

Turkey's parliament on Oct. 17 authorized the government to attack Iraqi bases of the Kurdistan Workers' Party, or PKK, which the U.S. and European Union both regard as a terrorist organization. Troops are massed on the border after PKK attacks that have killed at least 40 Turkish soldiers and civilians this month. Eight soldiers are also missing, the Turkish army said.

An assault on Iraq ``does not necessarily mean sending in ground troops,'' Erdogan said yesterday. ``There are various ways of doing it.''

General Yasar Buyukanit, the Turkish chief of staff, has called for strikes on Iraq; that increases pressure on Erdogan's government, which has been feuding with the army over its role as self-appointed guardian of secularism. Meanwhile, Iraqi Foreign Minister Hoshyar Zebari said his country will halt oil exports through Turkey if attacked.

`Break Up'

The U.S. and Iraq ``have to break up the PKK's camps and hand over the group's leaders,'' Erdogan told reporters on Oct. 19. The U.S. and Massoud Barzani, head of the Iraqi Kurdish regional government, have so far shied away from cracking down in what is the only relatively stable area of Iraq.

Turkish Foreign Minister Ali Babacan flew to Baghdad today to press Iraqi leaders to crack down on the group. Turkish artillery and warplanes yesterday bombarded the border area, the Sabah newspaper reported, citing witnesses.

Erdogan may be hesitating to attack due to the limited success of past incursions. Turkey's armed forces launched 24 major raids into Iraq prior to 1999, some of which involved as many as 50,000 troops. While those attacks destroyed PKK bases, the group was able to rebuild.

The PKK, which has an estimated 3,500 fighters in northern Iraq, has been waging a two-decade war for autonomy of Kurdish regions in Turkey that has left about 40,000 dead, mostly Kurds. About 12 million Kurds live in Turkey, a country of 74 million.

Raise the Cost

``The operation is not going to kill the PKK,'' said Soner Cagaptay, an analyst at the Washington Institute for Near East Policy. ``If the infrastructure is destroyed, Turkey will win for perhaps six months.''

Michael Rubin, a former U.S. Defense Department official who was stationed in Iraq from 2003 to 2004, said that ``the goal might not be to defeat the PKK, but to raise the costs for Barzani.''

Rubin, who is now with the American Enterprise Institute, a Washington research organization, said in an interview: ``Turkey is ratcheting up the costs of doing business with the PKK.''

PKK fighters often come down from their mountain bases to buy food and gasoline for their power generators, a supply line that Barzani may be forced to cut, Rubin said.

Turkey in 1998 threatened Syria with military action if it didn't force PKK leader Abdullah Ocalan to leave the country. Ocalan fled and in 1999 was captured by Turkish commandos.

Limited Strikes

Some experts predict that if Turkey does attack the PKK, it will opt for limited air and artillery strikes rather than a massive ground invasion.

According to one scenario, Turkey would first use its warplanes, mostly F-16s and F-4 Phantoms, and artillery to bombard PKK hideouts. If that doesn't succeed, Turkey might send in commandos to fight the guerrillas.

``It would be a limited operation with limited goals and a limited duration as they try and avoid a quagmire like Israel found in Lebanon,'' said Fadi Hakura, a Turkey analyst at Chatham House, a foreign-policy research institute in London.

If the government does decide on a large-scale land invasion, possibly tens of thousands of soldiers would storm across the border, Cagaptay said. The AEI's Rubin said Turkish forces would likely avoid densely populated areas where they would encounter large numbers of hostile residents.

Any military intervention would also serve as a message to Iraqi Kurds in autonomous northern Iraq. The Turkish government is alarmed over the prospect of Iraqi Kurds gaining control of the oil-rich northern city of Kirkuk, which would make a breakaway Kurdish state more economically viable. Its establishment might inflame nationalist passions in mainly Kurdish southeastern Turkey.

Even if diplomacy forestalls a major invasion now, there's no telling whether it will continue to in the face of Turkish public opinion. ``We're still just one bomb away from a crisis,'' Rubin said.

To contact the reporter on this story: Louis Meixler in Istanbul at lmeixler@bloomberg.net