Baghdad: The UN special envoy to Iraq said on Saturday the country could plunge into chaos if its divided parliament fails to move forward on forming a government in its next session set for Sunday.

Nickolay Mladenov called on all lawmakers to attend the session.

Lack of progress on choosing the top three government posts — president, prime minister, and speaker — “will only serve the interests of those who seek to divide the people of Iraq and destroy their chances for peace and prosperity,” he said in a statement.

On Friday, the Kurdish region claimed disputed northern oilfields in another blow to efforts to forge a united front against a jihadist-led onslaught, as twin bombings killed 30 people.

The escalating row between Baghdad and the Kurds and the blasts in disputed Kirkuk province came just before the parliamentary session.

With political disputes deepening and militants on the attack, the US embassy in Baghdad issued a sharp rebuke to Iraqi politicians, saying any additional delays or escalation would only play into the insurgents’ hands.

The oilfield takeovers come after Kurdish peshmerga fighters moved into stretches of disputed northern areas vacated by Iraqi forces during the initial militant offensive last month, and regional president Massoud Barzani has said they will stay there.

The escalating war of words between Prime Minister Nouri Al Maliki and the Kurds has already cast a pall over the parliamentary session slated for Sunday, and Kurdish ministers said Al Maliki’s stance “only served the enemies of Iraq and the terrorists” and announced they were boycotting cabinet sessions.

Deputy Prime Minister Hussain Al Shahristani has stepped in as acting foreign minister in place of Hoshyar Zebari, a long-serving Kurdish minister boycotting the cabinet, a senior official said.

As the Baghdad-Kurdish row deepened, militants captured multiple areas west of Anbar provincial capital Ramadi in fighting that began on Thursday afternoon, killing 11 police, bombing a police station and capturing another, an officer and a doctor said.

Meanwhile, authorities say some 4,000 volunteers are being dispatched to an embattled city west of Baghdad to help bolster government forces fighting militants there.

Gen Rasheed Flayeh, the commander of operations in Anbar province, says 2,500 of the reinforcements arrived on Friday in Ramadi, and the rest are expected to arrive on Saturday.

Ramadi is the capital of Anbar, a predominantly Sunni province and one of the most active fronts in Iraq. Militants overran parts of Ramadi early this year before the government reasserted its control.