Baghdad, Iraq ? Shiite leaders refused to sign an interim constitution after Iraq’s top Shiite cleric rejected portions of the charter, in a last-minute dispute that wrecked a planned signing ceremony Friday and marred a landmark in the U.S. plans to hand over sovereignty to the Iraqis.

A spokesman for one of the Shiite parties said no signing would take place before Monday, giving time for members to consult with Shiite Grand Ayatollah Ali al-Husseini al-Sistani — who has already forced two major revisions in U.S. plans to transfer power to the Iraqis.

The maneuver by five Shiite members of the Iraqi Governing Council broke the unity that the body showed earlier this week when it overcame deep differences to unanimously agree on a draft of the charter.

It also highlighted the power that al-Sistani wields over the political process because of his considerable influence over Iraq’s Shiite majority.

A statement distributed early today by the Governing Council said the members would reconvene Monday “to finalize” outstanding issues “and sign” the interim charter. However, it was unclear whether the final hurdles could be overcome according to the statement’s timetable.

Along with top U.S. administrator L. Paul Bremer, council members negotiated in private in an attempt to resolve the Shiite objections. But seven hours after the ceremony had been set to take place, a coalition spokesman said no deal was reached Friday.

The council’s squabbles squandered an enormous public relations and security effort for the ceremony, a stinging embarrassment for the U.S.-led occupation authority and its hand-picked Governing Council. Earlier, Bremer had appeared on morning television shows in the United States, touting the constitution on CNN’s “American Morning” as “an extraordinary document, which is really unprecedented in Iraq’s history.”

School children practice singing the Iraqi National Anthem behind a table with 25 pens and an empty chair lying idle in the middle of the lobby of the Convention Center for the historic new Iraqi interim Constitution in Baghdad, Iraq. The signing ceremony by the 25-member Iraqi Governing Council was delayed for more than five hours and then canceled after Shiite leaders refused to sign the interim constitution. Iraq's top Shiite cleric had rejected portions of the charter.

U.S. and Iraqi officials had planned an elaborate ceremony for the signing, full of symbols of Iraqi unity, that was left a shambles. A map of the country was emblazoned with the slogan “We all participate in the new Iraq.” Twenty-five fountain pens, one for each member, were lined up on an antique desk belonging to King Feisal I, Iraq’s first monarch.

Children wearing traditional costumes representing Iraq’s main ethnic groups were brought in for the occasion. With the audience waiting for the signing to take place, the children went ahead on stage and sang a repertoire of patriotic songs.

At the same time, helicopters swarmed the skies around the convention center, scouting for would-be attackers.

The attacks never materialized, but the meeting was sabotaged anyway.

The Shiite objections focused on two clauses in the document: one that effectively gives the Kurds a veto over a permanent constitution due to be put to a referendum next year and another on the shape of the presidency in a future government, said Hamed al-Bayati, a senior official.