BAGHDAD (Reuters) – Iraq”s Shi”ite-led government on Tuesday ruled out any major change to a draft constitution that parliament looks set to pass this week in the teeth of minority Sunni objections that it could ignite civil war.

&#34The draft that was submitted is approximately the draft that will be implemented,&#34 government spokesman Laith Kubba said after parliament received the text before a midnight deadline. The assembly put off a vote for three days to let tempers cool.

Sunni leaders, who largely shunned a January election that gave Shi”ites and Kurds control of parliament, quickly indicated they would try to mobilise support for a &#34No&#34 vote in the October referendum on the charter.

President George W. Bush said Iraq”s Sunnis had to decide what kind of society they wanted to live in. &#34This talk about Sunnis rising up, I mean the Sunnis have got to make a choice. Do they want to live in a society that”s free, or do they want to live in violence?&#34 he told reporters in Idaho.

The constitution will be rejected if two thirds of voters in three or more of Iraq”s 18 provinces vote &#34No&#34. The Sunnis are a clear majority in at least three provinces in the heartland of the insurgency: Anbar, Salaheddin and Nineveh.

A Sunni delegation met Iraq”s Independent Electoral Commission to discuss ways of ensuring participation in those three regions, the commission said in a statement.

President Jalal Talabani, who has brought Iraqi leaders together for weeks in a bid to keep the political process on track and defuse a Sunni insurgency, renewed mediation efforts.

A statement from his office said the Kurdish leader urged all Iraqi sects to unite on the issue of the constitution.

But all sides held fast to their positions.

The Shi”ite head of the parliamentary drafting committee again made clear he did not intend to reopen contentious clauses such as those on autonomous &#34federal&#34 regions which Arab Sunnis say discriminate against them and could break up the state.

Humam Hamoudi said the Sunni negotiators brought in from outside parliament were not representative and the assembly should now submit the draft to a referendum.

U.S. diplomats, under pressure from Washington to keep Iraqi negotiators to a timetable laid down under American supervision last year, say they will go on working for a consensus that can draw the once-dominant Sunnis away from violent opposition.

But one participant in the talks said a comprehensive deal would require a Sunni change of heart. &#34The only possible change now is that the Sunnis become convinced on federalism,&#34 said Jalal al-Din al-Sagheer, a Shi”ite cleric on the drafting team.

Shi”ites and Kurds said they might offer minor concessions, but were ready to use muscle to push through the draft.

&#34If it passes, there will be an uprising in the streets,&#34 Sunni negotiator Saleh al-Mutlak said after the brief sitting.

&#34We will campaign … to tell both Sunnis and Shi”ites to reject the constitution, which has elements that will lead to the break-up of Iraq and civil war,&#34 Soha Allawi, another Sunni on the drafting committee, told Reuters.

Iraq”s government hopes the constitution will divert more Sunnis from insurgency into peaceful politics. It called on Arab countries to restore full diplomatic relations with Baghdad and said it would set up a protected zone for them to live in.

&#34Arab states should not hesitate to restore diplomatic relations in a normal manner and should take a decisive and strong position condemning strongly all terrorist operations in Iraq,&#34 the Iraqi envoy to the Arab League, Raad al-Alousi, told reporters in Cairo.

But fresh violence underlined what a tough challenge the government is facing.

A suicide bomber killed a U.S. soldier, an American contractor and four Iraqi security guards at a joint centre in a town north of Baghdad, the U.S. military said in a statement.

The attack in Baquba also wounded nine U.S. soldiers, four Iraqi police officers and six Iraqi civilians, the statement said. Such attacks have raised fears that insurgents are infiltrating the Iraqi military and security forces.

The Baquba violence came after three car bombs exploded in quick succession near U.S. forces in Ramadi, west of Baghdad, in an apparently coordinated strike by insurgents, police and witnesses said. There was no immediate word on casualties.

In Ad Dawr, close to Tikrit, Saddam Hussein”s home town, hundreds of Sunnis demonstrated against the draft constitution. &#34Long live the honourable insurgency,&#34 the crowd yelled.

Some Shi”ites, notably radical cleric Moqtada al-Sadr, also reject federalism. But government-run television showed wild rejoicing in the Shi”ite holy city of Najaf after news of the ruling coalition”s plans to force through its charter.

Secular Shi”ites, including a party led by U.S.-backed former interim Prime Minister Iyad Allawi, have voiced doubts at the draft constitution being pushed through parliament.

The draft makes Islam &#34a main source&#34 of law, in an apparent compromise between Islamist Shi”ites and secular Kurds.