WASHINGTON (AFP) - US Vice President Joe Biden urged leaders of Iraq's feuding political and sectarian factions Sunday to convene a "dialogue" to head off a worsening political crisis.

Biden, Obama's pointman on Iraq, has made a flurry of calls to Iraqi leaders this week, urging them to mend their fences after the  Nuri al-Maliki accused his vice president Tareq al-Hashemi of hiring bodyguards to run a death squad. In calls to Maliki on Sunday and to Kurdish leader Massud Barzani, Biden "exchanged views... on the current political climate in Iraq and reiterated our support for ongoing efforts to convene a dialogue among Iraqi political leaders," the WHouse said in a statement.

Biden also offered condolences on a spate of attacks in Baghdad on Thursday that killed over 60 people. The strikes and the growing political row have heightened sectarian tensions just a week after the last US soldier of a garrison that once numbered 170,000 left Iraq and entered Kuwait a week ago.

Hashemi, holed up at an official guesthouse of Iraqi President Jalal Talabani in the country's autonomous Kurdish region after an arrest warrant was issued against him, acknowledged earlier that his guards may have carried out attacks. But he has steadfastly denied any involvement.

Asked if he would return to Baghdad to face trial, Hashemi told AFP: "Of course not," raising the prospect of fleeing Iraq. The 69-year-old attributed his refusal to travel to the capital to poor security and the politicization of the justice system.

Iraqiya, the bloc of Hashemi and deputy premier Saleh al-Mutlak that is part of Maliki's national unity government, has boycotted parliament and the cabinet in protest at Maliki's alleged centralization of power.

Meanwhile The New York Times, citing senior US administration officials, reported that the United States is weighing a far more subdued role in Iraq, and has no intention to send US troops back to the country.