A suicide attacker driving a car bomb killed at least five people when he detonated his payload at the interior ministry in central Baghdad on Monday, medical officials said.

At least 27 others were wounded in the 7:30 am (0430 GMT) attack in the Bab al-Sharji neighbourhood. The nearby Neurological Hospital took in five dead and 13 wounded, while al-Kindi Hospital treated 14 injured, officials at the two hospitals said.

The attacker took advantage of interior ministry guards opening the compound's main gates to allow in electrical maintenance workers to ram his explosives-packed car through and set it off, a ministry official said, speaking on condition of anonymity.

The blast came after violence across Baghdad on Thursday killed 60 people.

Iraq is mired in political dispute with authorities calling for the arrest of Sunni Arab Vice President Tareq al-Hashemi on charges he ran a death squad, accusations Hashemi denies.

Prime Minister Nuri al-Maliki has also called for the sacking of his Sunni deputy Saleh al-Mutlak, who has denounced the premier as a dictator "worse than Saddam Hussein".

The Sunni-backed Iraqiya bloc, to which both Hashemi and Mutlak belong, has boycotted the cabinet and parliament.

US Vice President Joe Biden had spoken by phone on Sunday with al-Maliki about violence in Baghdad and concerns about the political climate in Iraq following the US troop pull-out, the White House said.

Biden, who also spoke with Kurdistan Regional Government President Massoud Barzani, stressed in the calls that the United States supports "ongoing efforts to convene a dialogue among Iraqi political leaders," the White House said in a statement released during President Barack Obama's holiday in Hawaii.

Biden has played a leading diplomatic role alongside the US military's departure from Iraq this month, traveling to Iraq and engaging Iraqi leaders about signs of rising sectarian tensions in the country that Washington invaded in 2003