Turkey and Iraq have agreed on a deal to allow Turkish forces to cross into Iraq to pursue Kurdish rebels, media reports say.
PKK has been labelled a terrorist group by Turkey, the US and the EU
A security accord would be signed on Thursday, an Iraqi official confirmed.
Turkey has warned Iraq to crack down on the Kurdistan Workers' Party (PKK) within its borders or face a possible incursion by Turkish troops.
Tens of thousands of people have died in the insurgency, including at least 80 Turkish troops this year.
A deal was hammered out in talks between Iraqi Interior Minister Jawad Bolani and his Turkish counterpart Besir Atalay in the Turkish capital, Ankara.
Iraqi and Turkish officials confirmed the agreement would be signed on Thursday, but would not elaborate on the details.
Local Turkish television station NTV reported that under the accord, Turkish forces could cross into Iraq for small-scale "hot-pursuit" operations to chase the armed rebels after seeking permission from Iraqi authorities.
"The security agreement covers many issues related to the extradition of wanted suspects and activating security co-operation," Mr Bolani said.
"An enemy of the Turkish people and democracy in Turkey is an enemy of the Iraqi people and democracy in Iraq."
Turkey says about 4,000 PKK fighters are in Iraq's north.
In August, the two countries signed a memorandum of understanding on security, agreeing to "expend all efforts" to oust the fighters from Iraqi Kurdistan.
The PKK has been labelled a terrorist organisation by Turkey, the US and the EU.
It has been fighting for an ethnic homeland since 1984 in an area covering parts of Turkey, Iraq, Syria and Iran.