ISTANBUL/ANKARA (Reuters) - Turkish President Tayyip Erdogan said on Wednesday he feared a U.S.-Russian ceasefire plan would do little more than benefit Syrian President Bashar al-Assad and accused the West, Russia and Iran of only seeking to further their own interests.
The United States and Russia have announced plans for a cessation of hostilities in Syria to take effect starting on Saturday. But rebels backed by Saudi Arabia and Turkey have expressed doubts about the proposal, which excludes attacks by the Syrian army and its Russian backers on the jihadist groups Islamic State and the al Qaeda-linked Nusra Front.
"The West, the United States, Russia, Iran, the European Union and United Nations have unfortunately not managed to stand tall by the honor of humanity," Erdogan said in a speech in Ankara broadcast live on television.
"On the contrary, all these countries, because of their own calculations, have permitted, directly or indirectly, the killing of nearly half a million innocent people by the regime and its backers," he said.
NATO member Turkey has grown increasingly frustrated by the international response to Syria's five-year-old war, incensed by a Russian intervention which has tipped the balance of power in favor of Ankara's arch-enemy Assad and by U.S. support for a Kurdish militia it sees as a hostile insurgent force.
Relations with Moscow hit a nadir after Turkey shot down a Russian jet near the Syrian border last November, while ties with Washington are at their most strained for years.
The rebels fear Russia will use the exclusion of attacks on jihadists like Islamic State as a pretext to bomb them. Erdogan said the ceasefire should also exclude attacks on the Kurdish YPG militia, which Ankara views as a terrorist group.
"If the identification of who is from which opposition group in the region will be carried out by Russia, the Assad regime and structures like the YPG, then that is a grave situation," Erdogan said.
Syria's opposition High Negotiations Committee (HNC), which groups Assad's political and armed opponents, said on Monday it accepted "international efforts for a cessation of hostilities", but only on the condition that previous demands including an end to blockades and the bombardment of civilians were fulfilled.
The grouping's chief negotiator said on Wednesday it had yet to commit to the U.S.-Russian plan.
Turkey's stance on the Syrian war is becoming increasingly intertwined with the battle it is waging in its own southeast against militants from the Kurdistan Workers Party (PKK), which has fought a three-decade insurgency for Kurdish autonomy.
Ankara views the YPG militia and its PYD political wing, which have enjoyed U.S. backing in the fight against Islamic State in Syria, as a hostile insurgent force with deep logistical and operational ties to the PKK.
Like Ankara and the European Union, the United States lists the PKK as a terrorist group. But it sees the YPG as a useful ally and has indicated it will continue to work with them.
"What are they saying? The PYD and YPG, they fight against Islamic State and that’s why support them? That is a great lie," Erdogan said. He has repeatedly called on Washington to decide who its allies are - Turkey or the Kurdish militia.
Erdogan and Prime Minister Ahmet Davutoglu have both said the YPG, working with Kurdish militants in Turkey, were responsible for a suicide bombing that killed 29 people, most of them soldiers, in the capital Ankara last week.
A DNA report suggested the main perpetrator was Turkish, not a Syrian Kurdish YPG fighter as initially claimed by the government, but two security sources told Reuters on Wednesday that he had entered Turkey from Syria in July 2014 using a fake ID.
The Turkish armed forces shelled YPG positions in northern Syria in the days after the Ankara bombing and launched air strikes on PKK camps in northern Iraq, as the government vowed that those responsible would pay the price. Washington urged Ankara to stop shelling the YPG.
Clashes have also continued inside Turkey, where violence in the southeast is at its worst since the 1990s. Military helicopters killed nine PKK militants near the border with Syria on Wednesday, security sources said.
In its annual report on Wednesday, Amnesty International said round-the-clock curfews had left civilians in some areas in Turkey's southeast unable to access basic rights such as food, education and medical care. The government has blamed the militants for bringing their armed campaign to urban centers and has said military operations are not targeting civilians.
Additional reporting by Ayla Jean Yackley and David Dolan in Istanbul, Orhan Coskun in Ankara; Writing by Nick Tattersall; Editing by Andrew Heavens and Sonya Hepinstall