RMEILAN, Syria (Reuters) - Syria’s Kurdish-controlled northern regions voted to seek autonomy on Thursday, drawing rebukes from the Damascus government, neighboring power Turkey and Washington over a move that could complicate U.N.-backed peace talks.

Bureau members of a preparatory conference to announce a federal system discuss a "Democratic Federal System for Rojava - Northern Syria" in the Kurdish-controlled town of Rmeilan, Hasaka province, Syria March 16, 2016. REUTERS/Rodi Said

The vote to unite three Kurdish-controlled provinces in a federal system appears aimed at creating a self-run entity within Syria, a status that Kurds have enjoyed in neighboring Iraq since the fall of Saddam Hussein in 2003.

The proclamation is an open challenge to many of the sides in Syria’s five-year-old civil war, as well as their international sponsors, who have mainly been battling for control of what they say must remain a unified state.

The Kurds, who enjoy U.S. military support, have beaten back Islamic State fighters to control swathes of northern Syria, but the main Syrian Kurdish party, the PYD, has so far been excluded from peace talks that began this week in Geneva.

The three Kurdish-controlled regions agreed at a conference in Rmeilan in northeast Syria to establish the self-administered “federal democratic system of Rojava - Northern Syria”, officials announced. Rojava is the Kurdish name for north Syria.

Officials said at a news conference they intended to begin preparations for a federal system, including electing a joint leadership and a 31-member organizing committee which would prepare a “legal and political vision” for the system within six months.

A document seen by Reuters, issued at the meeting, said the aim was to “establish democratic self-administered regions which run and organize themselves ... in the fields of economy, society, security, healthcare, education, defense and culture.”

SWIFT TO DENOUNCE

Both the government of President Bashar al-Assad and Turkey, a regional heavyweight that is one of Assad’s strongest enemies, were swift to denounce the declaration.

“Any such announcement has no legal value and will not have any legal, political, social or economic impact as long as it does not reflect the will of the entire Syrian people,” state news agency SANA cited a foreign ministry source as saying.

An official in Turkey said: “Syria must remain as one without being weakened and the Syrian people must decide on its future in agreement and with a constitution. Every unilateral initiative will harm Syria’s unity.”

Even Washington, which has backed Kurdish fighters with air strikes on Islamic State targets, was displeased.

“We don’t support self-ruled, semi-autonomous zones inside Syria. We just don’t,” said State Department spokesman John Kirby.

“What we want to see is a unified, whole Syria that has in place a government that is not led by Bashar al-Assad, that is responsive to the Syrian people. Whole, unified, nonsectarian Syria, that’s the goal.”

Turkey fears growing Kurdish sway in Syria is fuelling separatism among its own minority Kurds, and considers the main Syrian Kurdish militia to be an ally of the PKK, which has fought an insurgency for Kurdish autonomy in southeast Turkey.

The PYD has consistently said it wants a model of decentralized government for Syria, not partition. The document agreed on Thursday stressed that the federal system would “guarantee the unity of Syrian territory”.

Nawaf Khalil, a former PYD official, played down parallels between Kurdish aspirations in Syria and Iraq, saying Thursday’s announcement was a joint move taken together with the region’s other ethnic communities.

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“The experience resulted from discussions with Arabs and Assyrians, Chechens, Armenians, Turkmen. There is a special case in Rojava, it is not like the path taken in Iraq,” he said.

KURDISH CONTROL

Syrian Kurds effectively control an uninterrupted stretch of 400 km (250 miles) along the Syrian-Turkish border from the Euphrates river to the frontier with Iraq. They also hold a separate section of the northwestern border in the Afrin area.

The areas are separated by roughly 100 km (60 miles) of territory, much of it still held by Islamic State.

A U.S.-backed force which includes Kurdish YPG fighters has been battling Islamic State and other militants, making some gains in Raqqa, Hasaka and Aleppo provinces. Kurdish official Idris Nassan said those “liberated” areas were included in Thursday’s agreement.

On Saturday, Syria’s government in Damascus ruled out the idea of a federal system for the country, just days after a Russian official said that could be a possible model. Russia’s five-month military intervention in Syria helped turn the tide of Syria’s war back in Assad’s favor.

President Vladimir Putin, who has announced the withdrawal of most Russian forces, said on Thursday Moscow’s intervention had created the conditions for Syria’s peace process.

The United Nations Syria envoy Staffan de Mistura, who is convening the peace talks in Geneva, suggested last week that a federal model for Syria could be discussed during negotiations.

“All Syrians have rejected division (of Syria) and federalism can be discussed at the negotiations,” he told Al Jazeera television.