Iraq on Thursday rejected a key element of an accord to bring an end to a long Kurdish uprising in Turkey - offering refuge to rebel fighters in country’s north.

In March, the Kurdistan Workers Party, or PKK, announced a deal to end a nearly three-decade conflict in turkey that has killed tens of thousands of people. The deal was reached in talks between imprisoned PKK leader Abdullah Ocalan and the Turkish government.

The refuge offer came from Iraq’s Kurdish region, which enjoys limited independence from the central Iraqi government in Baghdad. Iraqi Kurds were involved in the talks with Turkey.

The prospect of additional fighters joining the Kurdish forces in Iraq’s north could add tension to already souring relations with Baghdad. The two sides are in conflict over contested areas, including key oil-producing sectors.

As part of the accord, the PKK rebels agreed to a gradual retreat from Turkish territory to Iraq’s Kurdish region. On Thursday, Baghdad rejected that.

“The Iraqi government welcomes any political and peaceful settlement to the Kurdish cause in Turkey to stop the bloodshed and violence between the two sides and adopt a democratic approach to end this internal struggle,” said a statement issued by the Iraqi Foreign Ministry.

“But at the same time ... it does not accept the entry of armed groups to its territories that can be used to harm Iraq’s security and stability,” the ministry said.

PKK, considered a terror group by Turkey and its Western allies, is believed to have between 1,500 and 2,000 fighters inside Turkey, in addition to several thousand more based in northern Iraq, which they use as a springboard for attacks in Turkey.

To ease Baghdad’s concerns, PKK spokesman, Ahmet Deniz assured the Iraqi government that the plan would boost democracy and stability in the region.

“The (peace) process is not aimed against anyone, and there is no need for concerns that the struggle will take on another format and pose a threat to others,” Deniz told The Associated Press in a phone interview.

“A democratic resolution will have a positive effect on the region,” Deniz said. “We understand the concerns, but the process is related to the resolution of the Kurdish issue and won’t cause harm to anyone.”

The statement came a day after PKK rebels started withdrawing to bases in the Iraqi mountains. It was not clear if the Baghdad government would try to stop the process, expected to take several months.

Deniz confirmed that the PKK’s withdrawal process began on Wednesday. He gave no details on the numbers of fighters that had begun to retreat or if any had crossed into Iraq.

Iraqi and Turkish officials were not immediately available for comment.

PKK has sought greater autonomy and more rights for Turkey’s Kurds. The armed conflict between the two sides began in 1984.

In addition to the dispute over developing oil resources, the Kurds and the central government in Baghdad have been in a long-running dispute over lands claimed by the Kurds, power-sharing and rights to develop other natural resources.

Along with Sunni Arabs, the Kurds accuse Iraq’s Shiite Prime Minister, Nouri al-Maliki, of amassing power in his hands and marginalizing political opponents.

Relations between Iraq and Turkey have been strained since December, when fugitive Sunni Vice President Tariq al-Hashemi took refuge in Turkey following accusations by Shiite-led government that he was running death squads. Turkish officials rejected Baghdad’s request to hand over al-Hashemi, who was tried and convicted in absentia.

Turkish support for Sunni-led anti-government protests and a unilateral energy deal with Iraqi Kurds has added tension to relations between Baghdad and Ankara.