BAGHDAD (AP) -- Iraq's embattled Prime Minister Nouri al-Maliki is taking his struggle to keep his post to the courts after announcing he will file a legal complaint today against the country's newly elected president.
The deadlock over a new government has plunged Iraq into a political crisis at a time it is fighting a land grab by militants from the Islamic State in the country's north and west.
Senior U.S. officials said today that the Obama administration, which launched airdrops and airstrikes last week to support Kurdish and Iraqi forces battling the militants, has begun directly providing weapons to Kurdish peshmerga forces who have started to make gains against the al-Qaida breakaway group.
Al-Maliki has resisted calls for his resignation and the political infighting could hamper efforts to stem advances by the Sunni militants who have seized a large swath of northern and western Iraq in recent weeks.
In a televised speech after midnight Sunday, al-Maliki declared he will file a legal complaint against the new president, Fouad Massoum, for committing "a clear constitutional violation."
The prime minister said the president, who was elected by parliament, is obstructing al-Maliki's re-election and has carried out "a coup against the constitution and the political process."
Al-Maliki's Shiite-dominated bloc won the most parliament seats in April elections and the prime minister sees himself as rightfully keeping the post for a third term. He accused Massoum of neglecting to name a prime minister by Sunday's deadline.
The late-night speech was al-Maliki's first since U.S. forces launched airstrikes and humanitarian airdrops in Iraq last week. A parliament session scheduled for today to discuss the nomination of the new prime minister was postponed until Aug. 19.
In a sign of spreading tensions, Iraqi special forces loyal to al-Maliki were deployed at Baghdad's main intersections today, police officials said. Two of the capital's main streets -- popular spots for pro and anti-government rallies -- were partially closed as hundreds of al-Maliki's supporters took to the streets.
"We are with you, al-Maliki," they shouted, waving posters of the incumbent premier, singing and dancing.
The government also enforced a heightened security alert across the city, the officials said, speaking on condition of anonymity because they were not authorized to talk to media.
It was not immediately clear when al-Maliki would submit his complaint, presumably in a Baghdad court today.
But his action raised concerns abroad.
The UN special representative for Iraq, Nickolay Mladenov, urged Iraqis to "exercise restraint at this dangerous time" adding that Iraq's "special forces should refrain from actions that may be seen as interference in matters related to the democratic transfer of political authority."
The U.S. airstrikes have reinvigorated Iraqi Kurdish forces battling the Islamic State in northern and western Iraq. Kurdish forces retook two towns from the Sunni militants on Sunday, achieving one of their first victories after weeks of retreating, a senior Kurdish military official said.
Kurdish peshmerga fighters were able to push the militants out of the villages of Makhmour and al-Gweir, some 28 miles from the Kurdish capital of Irbil, said peshmerga Brig. Gen. Shirko Fatih.
The United States launched a fourth round of airstrikes Sunday against militant vehicles and mortars firing on Irbil as part of efforts to blunt the militants' advance and protect American personnel in and around the Kurdish capital.
U.S. warplanes and drones have also attacked militants firing on minority Yazidis around Sinjar, which is in the far west of the country near the Syrian border.
President Barack Obama warned Americans on Saturday that the new campaign to bring security in Iraq requires military and political changes and "is going to be a long-term project."
Obama said Iraqi security forces need to revamp to effectively mount an offensive, which requires a government in Baghdad that the Iraqi military and people have confidence in.
Obama said Iraq needs a prime minister -- an indication that suggests he's written off the legitimacy of the incumbent, al-Maliki.
Critics say the Shiite al-Maliki contributed to the crisis by monopolizing power and pursuing a sectarian agenda that alienated the country's Sunni and Kurdish minorities.
A week ago, al-Maliki ordered the Iraqi air force to support Kurdish forces against the militants, in a rare instance of cooperation between Baghdad and the Kurdish regional government, which have for years been locked in disputes over oil and territory.
All the while, the country's humanitarian crisis is growing, with some 200,000 Iraqis recently joining the 1.5 million people already displaced from violence this year. British officials estimated Saturday that 50,000 to 150,000 people could be trapped on Sinjar Mountain, where they fled to escape the Islamic extremists, only to become stranded there with few supplies.
Associated Press writers Sinan Salaheddin in Baghdad and Matthew Lee in Sydney contributed to this report.