Iraqi leaders acknowledged they had failed yet again to agree on a coalition government despite 12 weeks of horse-trading since parliamentary elections saw Shiites and Kurds emerge the big winners.

“In principle we were to have announced the new government today, but last-minute details are preventing this,” said Jawad Maliki, deputy leader of the Dawa party of prime minister-designate Ibrahim al-Jaafari.

US and European leaders, after weeks of silence, urged the authorities in Baghdad to speed up the process.

US Secretary of State Condoleezza Rice expressed her concerns in a telephone call to Iraqi Kurdish chief Massud Barzani.

The Secretary, and Vice President Dick Cheney, also pressed for action during a meeting with Adel Abdel Mahdi, a leading Shiite chosen as one of Iraq’s two vice presidents.

“We and the Iraqis agree that everybody would be well served by having a government in place, not just on the security side but to deal with the whole range of challenges facing Iraq,” Deputy State Department spokesman Adam Ereli said.

Ibrahim al-Jaafari has been seeking to form a cabinet based on a broad coalition of Shiites, Kurds and Sunni Arabs, despite the fact that the Sunnis, who dominated Saddam Hussein’s regime and all previous Iraqi governments, largely boycotted the polls.

He appeared to have abandoned efforts to convince supporters of outgoing Prime Minister Iyad Allawi, a secular Shiite backed by Washington, to join his coalition.

Mr Allawi’s supporters say they would join a new government only if they were given five cabinet posts, including a deputy premiership.

Mr Allawi’s Iraqiya list took just 40 of the 275 seats in parliament in the elections. The United Iraqi Alliance took 146 seats, while the main Kurdish bloc took 77.

Mr Jaafari has also run into trouble with the National Front, an umbrella group of more than 30 Sunni factions that wants eight cabinet posts, including a deputy premiership.

Sunni-led factions have just 17 MPs.

The political calendar calls for a referendum on the constitution by October 15.

If the constitution is approved in time, general elections are to be held by December 15 and a new government installed by December 31.