"We said (in the memorandum of understanding) that we will cooperate against terrorist organisations, notably the PKK," Iraqi premier Nuri al-Maliki said at a joint press conference with Turkish counterpart Recep Tayyip Erdogan.

"We wish that this cooperation starts without delay... Terrorism should not hamper the development of our relations," he said.

Ankara has threatened a cross-border operation to strike at bases of the Kurdistan Workers' Party (PKK) in neighbouring northern Iraq if Baghdad and Washington fail to curb the rebels. The PKK has stepped up its attacks inside Turkey this year.

The two leaders said the memorandum of understanding paved the way for a security cooperation agreement between the two countries, to be finalised after high-level bilateral talks in the coming days.

Turkey says the PKK, considered a terrorist group by Ankara, Washington and much of the international community, enjoys free movement in northern Iraq, where it obtains weapons and explosives.

Turkey has accused the forces of Massud Barzani, who heads the autonomous Kurdish adminsitration there, of providing the PKK with weapons, possibly including ammunition received from the United States.

Observers here doubt whether Maliki's embattled government, which has virtually no authority in northern Iraq, can persuade the Iraqi Kurds to act against the PKK, whose bloody campaign since 1984 for self-rule in southeast Turkey has claimed more than 37,000 lives.

Maliki insisted Tuesday that the Iraqi Kurds should abide by agreements signed by the central Baghdad government.

"Iraqi Kurdistan is part of Iraq... Bilateral agreements are binding for them as well," he said.

"We are saddened that Turkey is subjected to terrorism and we will cooperate in this field," he added.

Ankara has long urged Baghdad to capture and hand over PKK members, close down organisations linked to the group and put the PKK on its list of terrorist organisations.

The planned bilateral security agreement entails cutting off financial and logistic support to the group, blocking its media broadcasts, and allowing for the extradition of rebels and exchange of intelligence, according to Turkish media reports.

In June, the Turkish army said there were some 5,000 PKK rebels in total, an estimated 2,800 to 3,100 of them based in northern Iraq.

The PKK has notably stepped up its attacks in the east and southeast of Turkey this year. In response, the army has reinforced its units in the region and amassed troops on the border with Iraq, fuelling speculation of an impending cross-border operation.

In the latest episode of violence, a soldier was killed and two pro-government militia wounded in a landmine blast overnight Monday blamed on the PKK in the southeastern province of Hakkari.

Washington has warned Ankara against an incursion into northern Iraq, wary that it may destabilise a relatively peaceful region of Iraq and fuel tensions between Turkey and the Iraqi Kurds, staunch allies of the United States.

Turkey also suspects Iraqi Kurds of harbouring designs to break away from Baghdad and set up their independent state which, it fears, would embolden the PKK.

Erdogan hailed his talks with Maliki as "very useful discussions that had very positive results."

The two sides had also signed a memorandum of understanding to boost cooperation in the energy sector and explored ways of boosting economic cooperation and trade, he said.

Maliki, who also met with President Ahmet Necdet Sezer, was to leave Wednesday morning and head for Tehran, where security issues were also expected to dominate his agenda.