Iraq's Foreign Minister Hoshyar Zebari warned on Saturday of the danger that the Syrian crisis might spill over into neighbouring states, and insisted that Iraq have a role in the future of Syria.

Iraqi Deputy Prime Minister Hussein al-Shahristani meanwhile expressed concern that extremists in Syria will promote sectarian strife in the region.

Syria, where President Bashar al-Assad's regime launched a brutal crackdown on opponents in March 2011 that has left thousands dead, shares a roughly 600-kilometre (372-mile) border with Iraq.

"Our main concern is the spillover of the crisis ... into neighbouring countries, and no country is immune from this spillover because of the composition of the societies ... the connections, the sectarian ethnic dimensions," Zebari told a news conference in Baghdad.

"If this conflict were to turn (into) an all-out sectarian or civil war, Iraq would be affected, Lebanon would be affected, Jordan will not be immune," as would also be the case with Turkey, he said, speaking alongside the foreign ministers of Poland, Sweden and Bulgaria, who were on a visit to Iraq.

"We don't want to see chaos reign, you see, in the region, in the neighbourhood, and that's why Iraq should have a say, a role in what is going to (happen) in Syria. No country can ignore or bypass Iraq in this regard," Zebari said.

A statement from Shahristani's office said that he had expressed concern in a meeting with the visiting European foreign ministers over "takfiris" in Syria, referring to those who declare others to be infidels, justifying their killing.

Shahristani said that Iraq supports "democratic change for the Syrian people," but also expressed "concern about takfiri partisans who are trying to push the Syrian people into sectarian conflict which will affect the region," the statement added.

A brutal Shiite-Sunni sectarian conflict tore across Iraq from early 2006, leaving tens of thousands of people dead.

Zebari also said Iraq was in contact with the Syrian opposition, including armed groups, but reiterated Iraq's opposition to providing weapons to either side in the conflict.

"Iraq has continuous contacts with the Syrian opposition sides, and we have meetings and contacts with the Syrian National Council ... and even with some military sides," he said.

But "providing the regime or the opposition with weapons leads to deepening and continuing the crisis."