Iraq's Kurds hope Monday's non-binding referendum on independence marks the start of a peaceful, negotiated break with Baghdad, but it may have instead placed them on a new collision course with Iraq and its neighbours.

Iraq's central government rejected the vote long before it was held, and Prime Minister Haider al-Abadi has warned of "followup steps to protect the unity of the country." Turkey and Iran have staged military drills on the borders of Iraq's Kurdish region, and Turkish President Recep Tayyip Erdogan has threatened to send in troops.

The vote was held peacefully, but the coming days could bring escalating unrest as the Kurds press ahead toward independence, something opposed by virtually the entire international community, including their close ally, the United States.

Initial results are expected Tuesday, with the official count announced later in the week.

The vote — likely to be a resounding "yes" when official results are revealed later this week — is not binding and will not immediately bring independence to the autonomous region.

Road to independence, or conflict

Kurdish officials say a "yes" vote will send a message Baghdad cannot ignore, paving the way for negotiations aimed at a peaceful exit. But Iraqi government officials maintain just the opposite, that the referendum will push the two sides further apart and make it even more difficult to resolve longstanding disputes.

Iraq Kurdish referendum

An Iraqi Kurdish man prepares to cast his ballot. (Khalid Mohammed/Associated Press)

The regional government has long been at odds with Baghdad over disputed territories like the oil-rich city of Kirkuk, which are controlled by Kurdish forces but outside their autonomous zone. They have also argued over the sharing of oil revenues, with the Kurds exporting through a Turkish pipeline over objections from Baghdad.

The conflict has been largely peaceful until now, but in recent days both sides have threatened to use military force to protect their interests. In Kirkuk, the epicentre of the territorial dispute, the governor imposed a nighttime curfew after the vote.

International repercussions

After the vote on Monday, UN Secretary General Antonio Guterres said in a statement, "The decision to hold the referendum in disputed areas, notably in Kirkuk, is particularly destabilizing."

Guterres also said he "regrets that the opportunity for serious negotiations to resolve outstanding issues" between the Iraqi and Kurdish governments "were not fully seized prior to this move."

The Kurds have been a close American ally for decades, and the first U.S. airstrikes in the campaign against ISIS were launched to protect Irbil. Kurdish forces later regrouped and played a major role in driving the extremists from much of northern Iraq, including Mosul, the country's second largest city.

The United States came out as an early opponent to the vote, initially urging it to be called off.

U.S. officials warned that the vote is likely to destabilize the region and take resources and attention from the fight against ISIS.

Iraq Kurdish Referendum

A girl dressed in the colours of the Kurdish flag accompanies her mother on voting day. (Bram Janssen/Associated Press)

Canada has taken a different approach. While Canadian officials have also long claimed to support a united Iraq, the Liberal government has remained relatively silent on the Kurdish referendum.

During an event in Toronto on Monday, Primer Minister Justin Trudeau said, "As a Quebecer, I'm very sensitive to other countries weighing in on internal decisions around the future of a country or separation questions.

"I was involved in two referendum campaigns in Canada where we very much appreciated foreign interlocutors not weighing in on what Quebecers should be choosing and what Canadians should be choosing."

Invasion threats from Turkey

Both Turkey and Iran condemned the vote, fearing it would inspire their own sizable Kurdish minorities, and both have carried out military drills this week on the borders of Iraq's Kurdish region.

Turkish President Recep Tayyip Erdogan said Monday that Kurdish independence was unacceptable, and a "matter of survival" for his country. Pointing to the military drills along the border, he said "we could arrive suddenly one night."

Turkey Kurdish Independence

Turkish President Recep Tayyip Erdogan, speaking during a meeting in Istanbul on Monday, threatened military intervention in Iraq in response to the referendum, and also suggested that Turkey could halt oil flows to the area. (The Associated Press)

Turkey has several ways of pressuring the Kurds short of military intervention. Much of the Kurdish region's oil exports flow through a Turkish pipeline, and Turkey is the region's main trading partner.

"Let's see where — and through which channels — will they sell their oil. We have the valve. The moment we shut the valve, that's the end of it," Erdogan said.

Ankara called on the international community and especially regional countries not to recognize the vote either and urged Iraq Kurdish leaders to abandon "utopic goals," accusing them of endangering peace and stability for Iraq and the whole region.

Mandate for Turkish military to intervene

On Saturday, Turkey's parliament met in an extraordinary session to extend a mandate allowing Turkey's military to send troops over its southern border if developments in Iraq and Syria are perceived as national security threats.

Erdogan's office said he and Russian President Vladamir Putin have spoken over the phone about the vote, and stressed the importance of Iraq's and Syria's territorial integrity.

His office said after Monday's phone call that Putin would visit Ankara on Thursday to discuss developments in the region, including the Kurdish referendum. There was no immediate confirmation from Moscow.

Syria's foreign minister also said his country doesn't recognize the referendum, saying Damascus rejects any measure that could break up neighbouring Iraq.

The Syrian state news agency Sana said Walid al-Moallem spoke on Sunday in New York. Syria has a large Kurdish minority that last week had its own vote as part of a move toward a federal system within Syria.

The war on ISIS

An armed conflict between Iraq and the Kurds would pit two close U.S. allies against each other and detract from their war against the Islamic State group.

Iraq Kurdish referendum

An Iraqi Kurdish woman casts her ballot. (Khalid Mohammed/Associated Press)

Iraqi and Kurdish forces succeeded in driving ISIS from the northern city of Mosul in July after a gruelling nine-month campaign, but the extremists still control pockets of territory in Iraq, and have a long history of exploiting political vacuums.

Masoud Barzani, the Kurdish regional president who has spearheaded the referendum, insisted ahead of the vote that Iraqi and Kurdish forces would continue to co-ordinate the fight against the extremists.

Political repercussions

The Kurdish push for independence is likely to weaken al-Abadi, who took office in 2014 on promises to unite the country, ahead of general elections slated for next year.

The referendum could strengthen hard-liners like former Prime Minister Nuri al-Maliki, who is widely believed to be seeking a return to power, as well as Iran-backed factions and militias. Al-Maliki went further than al-Abadi in his condemnation of the referendum, calling it a "declaration of war."

Although the vast majority of Kurds support independence in principle, many have objected to the referendum, viewing it as a cynical ploy by Barzani to hold onto power after his term expired in 2015. When parliament convened earlier this month, for the first time in two years, nearly half the lawmakers boycotted the session.

MIDEAST-CRISIS/IRAQ-KURDS

Kurdistan regional leader Massoud Barzani insisted ahead of the vote that Iraqi and Kurdish forces would continue to co-ordinate the fight against ISIS. (Azad Lashkari/Reuters)

Barzani is betting that the referendum will strengthen his hand against his political opponents, but he also stands to take most of the blame if a crisis erupts.

Kurdish quest for independence 

At a news conference, Barzani detailed the abuses Iraq's Kurds have faced by Iraqi forces, including killings at the hands of former leader Saddam Hussein's army that left more than 50,000 Kurds dead.

Iraqi Kurds have long dreamed of independence — something the Kurdish people were denied when colonial powers drew the map of the Middle East after the First World War. The Kurds form a sizable minority in Turkey, Iran, Syria and Iraq.

In Iraq, they have long been at odds with the Baghdad government over the sharing of oil revenues and the fate of disputed territories like Kirkuk.