BAGHDAD, Iraq — A deal to bring Iraq's rebellious Sunni Muslim minority into the new Iraqi government fell through at the last minute yesterday, so the Cabinet was sworn in with seven posts, including the oil and defense ministries, vacant or filled only temporarily.

The breakdown marred the historic installation of Shiite Muslim leader Ibrahim al-Jaafari as prime minister, after elections on Jan. 30 and more than three months of intense political negotiations aimed at placating Iraq's feuding ethnic groups.

Negotiators have stumbled over how to bring Sunnis into the government after most Sunnis failed to vote in the election. The majority of Iraqis are Shiites, but they were brutally suppressed under the rule of Saddam Hussein, a Sunni.

Including credible Sunnis is considered key to any hopes of stemming Iraq's bloody insurgency, but Shiite negotiators have repeatedly rejected Sunni candidates with even remote ties to the old regime. Four Sunnis were among the 37 Cabinet members sworn in.

The transitional government is scheduled to run the country until December, when fresh elections are to be held, under the terms of the new constitution that the National Assembly will write.

If the assembly fails to complete the constitution by August, it may request a six-month delay that also would push back the next election.

Al-Jaafari appeared untroubled by the breakdown.

"We are not in a hurry," he said. "We want the choice to be acceptable to all the Iraqi people. ... We shouldn't turn this into a sectarian issue. My brothers will choose."

Late Monday night, Sunni politicians were assured that al-Jaafari and President Jalal Talabani had approved their picks for top Cabinet posts. The names of the agreed-upon Sunni ministers had already been aired on Arab satellite news channels, and seats on the podium for the swearing-in ceremony were plastered with some of their names.

But hours before the ceremony yesterday, the would-be ministers were told they'd been rejected, for reasons that still aren't clear.

Mijbal Sheikh Issa, who was slated to head the minerals-and-industry ministry, said Shiite and Sunni intermediaries said the latest objections came from "foreign entities," implying that the Bush administration had problems with the choices.

Yesterday afternoon, a delegation of Sunnis called an emergency meeting with British and U.S. Embassy officials at the Rasheed Hotel in the heavily guarded Green Zone. Issa, among those present, said the Western diplomats swore that there had been no intervention and sent a letter to Vice President Ghazi al-Yawer, a Sunni, saying the embassies had no objections to the proposed candidates.

The U.S. Embassy couldn't be reached for comment.

Two vice-prime-minister positions were left vacant, while five ministries were filled with temporary appointees.

Al-Jaafari will assume temporary control of the defense ministry, while a one-time Pentagon favorite, vice prime minister Ahmad Chalabi, will take on the all-important oil ministry.

The administration's most prominent Sunni, al-Yawer, did not attend the ceremony in what was widely interpreted as a protest of the failure to name more Sunni members to the Cabinet. Al-Yawer had warned that he would not attend unless a Sunni was appointed to the key post of defense minister, as al-Jaafari promised last week.

Two other Sunni ministers were absent, apparently to protest the dominant Shiite and Kurdish blocs' rejection of their candidates.

"We have decided as Sunni Arabs to [stay away] since there wasn't an agreement yet on all the names," said Azhar Abdel-Karim, the minister of state for women's affairs. "We thought we should all be sworn in at the same time."

The candidate for defense minister who was scuttled at the last minute was Ahmed al Rikan, a Sunni Arab from Mosul and a former brigadier general who served under Saddam but turned against him.

Members of the dominant Shiite bloc, the United Iraqi Alliance, implied that the Sunni ministerial candidates were unacceptable because they'd had ties to the former regime.

"We had three conditions for Sunni ministers," said Abbas al Bayati, an assembly member from the alliance. "They shouldn't have been part of Saddam's forces, which suppressed the 1991 uprising in the south. Also, they shouldn't have been engaged in the Anfal campaign suppressing the Kurds. And third, they shouldn't have been a high-ranked Baathist during the fall of the regime."

Al-Jaafari had hoped to give the defense ministry to a Sunni Arab as part of a strategy to persuade insurgents, mostly disaffected Sunnis, to lay down their arms. U.S. officials believe having a Sunni as defense minister is essential to the success of the new government.

Information from the Chicago Tribune

is included in this report.