Turkey has accused the regional Kurdish government in northern Iraq of harbouring fighters from the PKK.
"I think it is pretty difficult to say troops shouldn't [invade] when the Turkish soldiers are being killed, and their villages attacked"
Celtic, Karlstad, Sweden
Send us your views
The separatist group is said to use bases in the mountainous region for cross-border attacks as part of its 23-year campaign for self-rule in Turkey's mainly Kurdish southeast.
Rice told reporters while en route to Turkey: "We have certainly been concerned that anything that would destabilise the north of Iraq is not going to be in Turkey's interests, it is not going to be in our interests and it is not going to be in the Iraqis' interests. That's been the reason for urging restraint.
"But we understand the need to do something effective against this PKK threat ... The PKK is an enemy of the United States just like it is an enemy of the Turks."
Rice will meet Ali Babacan, Turkey's foreign minister and Abdullah Gul, the country's president, during her visit.
She will also hold talks with Tayyip Recep Erdogan, Turkey's prime minister, who is due to meet George Bush, the US president, in Washington next week to discuss how to tackle the PKK.
Ban Ki-moon, the UN secretary general, is also attending the talks in Istanbul.
Al Jazeera's Hoda Abdel Hamid, reporting from Istanbul, says the Turkish public's expectations of results are low.
She said: "Condoleezza Rice is entering unfriendly territory, as public opinion is strongly anti-American these days, as well demands of swift action against the PKK."
Both Baghdad and Washington strongly oppose any unilateral Turkish action in northern Iraq on the grounds that it would destabilise the only relatively calm region of the war-torn country.
Turkey has reportedly massed up to 100,000 troops on the border with Iraq and has threatened a military incursion to strike at PKK bases unless Baghdad and Washington promise to crack down on the fighters.
|The government in Iraq has asked Iran to |
help resolve the crisis [AFP]
The White House has offered Ankara "actionable intelligence" on the PKK.
"We have no time to lose. All instruments – diplomatic, political, socio-cultural and military - are on the table," Babacan said.
He also said that Turkey may restrict flights to northern Iraq.
The meeting is a follow-up to a conference held in the Red Sea resort of Sharm El-Sheikh in Egypt, in May where a pledge was made to stop foreign fighters from joining Iraqi militias.
Meanwhile, Tayyip Erdogan, the Turkish prime minister, is to meet with George Bush, the US president, in Washington on Monday.
Turkish troops have been engaged in major operations targeting the PKK since October 21 when a group of fighters, who Ankara says came from northern Iraq, ambushed a military unit, killing 12 soldiers and capturing eight.
The army says it has since killed 80 fighters on Turkish territory.
A top PKK commander on Thursday called on Ankara to present a peace plan that could end the group's rebellion, which has claimed more than 37,000 lives.
Turkey refuses to have any contact with or make any concessions to the PKK.
Source: Al Jazeera and agencies