Iraqi Kurdish lawmakers on Friday voted to hold an independence referendum set in motion by regional president Massud Barzani, who has kept open the option of postponing it under American pressure.
In the face of bitter opposition from Baghdad, 65 out of 68 lawmakers present voted in favour of the September 25 poll as opposition members boycotted the parliament's first session in two years.
After the show of hands, lawmakers stood to sing the Kurdish anthem while others raised flags to the sound of applause.
The vote was to give a legal framework to the referendum that has also stirred protests from neighbouring states, especially Turkey.
Washington opposes the referendum on the grounds that it would weaken Arab-Kurdish joint military operations which have helped send the Islamic State (IS) militant group into retreat in both Iraq and war-torn Syria.
The United States has proposed unspecified "alternatives" to which Barzani has pledged to give a rapid response.
"If they have a stronger alternative to the referendum, the Kurdish leadership will look at it, but if they want (us) to postpone the vote with no alternatives, we won't," Barzani, who set the referendum date in June, said Thursday.
The session was the regional parliament's first in two years, and Barzani's mandate as president of the autonomous Kurdish region in northern Iraq officially expired in 2015.
The Kurdish leadership, made up of Barzani's Kurdistan Democratic Party (KDP) and the Patriotic Union of Kurdistan (PUK) of Iraq's former president Jalal Talabani, have maintained that the three-year-old battle to drive back IS has made it impossible to hold fresh elections.
Two opposition parties -- the independent Goran, which has 24 seats in the 111-seat parliament, and Jamaa Islamiya, which is close to Iran and holds six seats -- said they would boycott the session.
Friday's session in Arbil followed two anti-referendum votes which passed earlier this week in the national parliament in Baghdad, both of which were boycotted by Kurdish legislators.
Analysts say the referendum plan, which has stirred Arab-Kurdish ethnic tensions, could mark the end of an era of cooperation during which Baghdad and Arbil battled IS together after it seized swathes of northern and western Iraq in the summer of 2014.
Turkey and Iran fear the referendum could stoke separatist aspirations among their own sizeable Kurdish minorities.
Ankara has warned of the "cost" to the Iraqi Kurds, whose economy is heavily dependent on oil exports via a pipeline running through Turkey to the Mediterranean.
On Thursday, the Baghdad parliament fired the governor of the northern province of Kirkuk, Najm Eddine Karim, over his provincial council's decision to take part in the non-binding Kurdish referendum.
The oil-rich province is disputed by Baghdad and Arbil and home to diverse communities including Arabs and Turkmens who oppose the vote.
Mixed regions such as Kirkuk are a highly sensitive issue in ethnically fragmented Iraq, with its Shia-dominated government in Baghdad and large Sunni Arab and Kurdish communities.
In Kirkuk province, the different communities have been arming themselves while numerous paramilitary forces have taken up positions north and west of Baghdad as joint units advance against the retreating IS militants.
In the city of Kirkuk, Kurdish peshmerga fighters have taken charge of security, while Shia paramilitary units have been deployed on the outskirts.
Hadi al-Ameri, head of the powerful Iranian-backed Badr organisation, has vowed to defend the unity of Iraq and warned that the Kurdish referendum could lead to partition and civil war.
Iraqi Kurdistan, whose people were brutally repressed under Saddam Hussein, won autonomy in 2005 following the dictator's ouster in a US-led invasion under a constitution which set up a federal republic in Iraq.
The referendum would "not necessarily lead to (an) immediate declaration of statehood, but rather to know the will and opinion of the people of Kurdistan about their future", Barzani said in February.
Kurdish leaders have since reiterated that a "yes" vote would pave the way for the start of "serious negotiations" with the Baghdad government.