Jalal Talabani, the Iraqi president, announced on Sunday that he would order parliament to convene on 12 March in a move designed to force a showdown in the dispute over the candidacy of Ibrahim al-Jaafari, the Shia prime minister, for a second term in office.
However, Talabani, a Kurd, was unable to count on the support of one of his vice-presidents, Adel Abd al-Mahdi, a Shia who narrowly lost in his own attempt for the prime minister's job by one vote.
The Shia faction decided to close ranks on Monday and Abd al-Mahdi has refused to sign for the moment.
Talabani had secured the backing of his other vice-president, Shaikh Ghazi Ajil al-Yawir, a Sunni who was out of the country.
The delay may seriously hinder Iraq's attempts at forming a new government, and increase speculation about whether the fledgling democratic process will be able to withstand continuing sectarian violence.
Threat to democracy
The sitting of parliament would have triggered a 60-day countdown to elect a new president and approve the nomination of al-Jaafari and sign off on his cabinet.
Nearly three months after an election hailed by the US as a significant milestone in Iraq's democratic process, the country's divided political factions are still fighting over the post of prime minister in the new government.
The Sunni Arab minority blames al-Jaafari for failing to control the Shia militiamen who attacked Sunni mosques and clerics after the 22 February Shia shrine bombing in Samarra.
Ongoing violence threatens Iraq's
move to democracy
Kurds are angry because they believe al-Jaafari is holding up resolution of their claims to the control of the oil-rich city of Kirkuk.
Leaders of all Iraq's major political factions scheduled a meeting for Tuesday evening in an attempt to untangle the religious and sectarian differences behind the crisis.
The leadership vacuum at the heart of Iraqi politics has been accentuated by the continuing violent attacks.
Away from the political wrangling, bombs killed 16 Iraqis and snipers assassinated the Sunni general in charge of forces protecting the capital, on Monday.
The bloodiest assault occurred in Baquba, where a car bomb targeting an Iraqi police patrol exploded near the mayor's office and a market, killing six people and wounding 23, including four patrolmen, police said.
Major-General Mibder Hatim al-Dulaimi, the Sunni Muslim in charge of patrolling Baghdad with his 6th army division, was killed when fighters fired at his convoy.
In other violence, bombs, mortar shells and gunfire also rocked the capital on Monday, ending a relative lull over the weekend.