* PKK comrades greet militants in valley near border
* Erdogan taking huge gamble with peace process
* More than 40,000 people killed in conflict since 1984 (Adds Iraqi statement, details, female militants)
By Isabel Coles
HEROR, Iraq, May 14 (Reuters) - Weary and caked in mud, the first group of Kurdish militants to leave Turkey under a peace plan to end three decades of war descended a mountain into Iraq on Tuesday to be met with embraces from PKK comrades.
Kurdistan Workers Party (PKK) fighters began leaving their positions in southeast Turkey last week following a March ceasefire declared by jailed leader Abdullah Ocalan to end a conflict that has killed 40,000 people, ravaged the region's economy and tarnished Turkey's human rights record.
The 15 men and women dressed in baggy green fatigues walked single file into a valley at Heror near Metina mountain. They carried Kalashnikov rifles and rucksacks with rolled-up sleeping mats on their backs.
"For seven days we were on the road and the conditions were very tough. There was snow, it didn't stop raining and the road was muddy," said one of the newly arrived guerrillas called Sorkhwein, a hand grenade visible inside her jacket.
The PKK is deemed a terrorist group by the United States and European Union as well as Turkey.
Ocalan was sentenced to hang after he was captured by Turkish special forces in 1999 in Kenya but this was commuted to a life term when Turkey abandoned the death penalty as part of reforms intended to open the doors of the EU.
The peace plan is a gamble for Prime Minister Tayyip Erdogan who could face a nationalist backlash before elections next year. But opinion polls currently show a high level of public support for a process that could bring a degree of stability to a turbulent area bordering Iraq, Iran and Syria.
Television footage of the militants' arrival in Iraq did not immediately feature on major Turkish broadcasters, apparently reflecting public sensitivities over the PKK issue.
"Our issue will be solved with the release of our leader Apo (Ocalan) from prison. Then everything will be solved," Sorkhwein said as the rebels warmed themselves around a campfire on which tea was brewing. Red, yellow and green PKK flags and a banner bearing Ocalan's moustachioed face hung in the background.
Sorkhwein was one of six female fighters in the arriving group, illustrating the important role played by women in the PKK insurgency and their wish to escape traditional gender-based roles in Kurdish society.
In some cases, a desire to avenge the killing of relatives was the motivation for women joining.
The PKK force is small but dogged, with 3,000-4,000 fighters in the mountains of northern Iraq and some 2,000 in Turkey, where they have targeted Turkish troops as well as bombed cities. The withdrawal is expected to take several months.
The group, accusing Turkey of violent repression of the Kurdish minority, launched its insurgency in 1984 with the goal of carving out a Kurdish state but subsequently moderated its aim to autonomy for the mainly Kurdish region of the southeast.
In talks pursued by Ocalan and Turkish officials since last autumn, Kurds have pressed for constitutional reform recognising the ethnic minority's cultural, political and linguistic rights with an end to the stress on 'Turkish identity' that marks the current charter.
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DRONES MONITOR WITHDRAWAL
Sorkhwein said the group did not see any Turkish military on the way but 21-year-old Welat Afrin, a Syrian Kurd who has been with the PKK for seven years, said Turkish reconnaissance drones had hovered overhead, apparently monitoring their journey.
The militants have accused the army of endangering the pullout, ordered by PKK commander Murat Karayilan last month, with drones and troop movements which they warned may trigger clashes.
"The journey was hard but with Apo as our leader nothing can break our will," Afrin said. "If there is a need for war we will fight. If there is no need, we will struggle politically."
He added that the militants could go and fight in Syria if Kurds there came under attack during the two-year-old conflict between President Bashar al-Assad and Syrian insurgents.
The withdrawal was being monitored in Turkey by the MIT intelligence agency and in northern Iraq by the Kurdish regional government, while Iraq's central government on Tuesday again voiced its objection to the withdrawal.
"The Iraqi government reiterates its rejection of the withdrawal and the presence of the PKK inside Iraqi territory, which is a blatant violation of the sovereignty and the independence of Iraq," a council of ministers statement said.
It said it would submit a complaint to the U.N. Security Council on the issue.
Turkey has pledged to maintain the fight against the PKK until they disarm but Erdogan said they will not be targeted during the pullout. The PKK has reported Turkish artillery strikes in recent weeks, with no reports of casualties.
Erdogan had demanded the rebels disarm before leaving but the PKK rejected this, fearing they could come under attack as they did in a previous pullback. The PKK has warned it will retaliate if the Turkish army launches operation against them.
The militants said it was now up to Ankara to push the peace process forward with reforms to address the grievances of Kurds, who make up around 20 percent of Turkey's 76 million population.
"We ask the Turkish side to be sincere with us so we can achieve the common interest," said Ciger Gewker, another of the arriving militants.
"The next step is up to Turkey. If they deal with our move in a positive manner it will be quicker," he said. (Writing by Daren Butler; Editing by Parisa Hafezi and Angus MacSwan)