UNITED NATIONS (AP) – The United Nations has expressed its concern to the Iraqi government that last-minute changes to the country”s electoral laws do not meet international standards, a U.N. spokesman said.

U.N. officials have been meeting with Iraqi authorities and are confident that Iraq will ultimately agree to sound electoral rules, spokesman Stephane Dujarric said Tuesday.

Sunni Arab leaders have threatened to boycott Iraq”s Oct. 15 vote on a new constitution because of new rules by the Shiite-led parliament, which make it nearly impossible for Sunnis to defeat the document at the polls.

&#34Ultimately, this will be a sovereign decision by the Iraqis and it”s up to the Iraqi National Assembly to decide on the appropriate electoral framework,&#34 Dujarric said. &#34That being said, it is our duty in our role in Iraq to point out when the process does not meet international standards.&#34

Dujarric said that as far as he knew, there had been no discussion between the United Nations and the Americans on the issue.

Election rules hold that the constitution will be defeated if two-thirds of voters in any three of Iraq”s 18 provinces vote against it, even if it wins a majority approval nationwide. Sunni Arabs have a sufficient majority in four provinces.

But on Sunday, parliament passed a new interpretation of the rules saying that two-thirds of registered voters must vote &#34no&#34, not just of those who actually cast ballots.

The interpretation raises the bar to a level almost impossible to meet. In a province of 1 million registered voters, for example, 660,000 would have to vote &#34no&#34, even if that many didn”t even turn out to cast ballots.

&#34We”ve relayed our concerns to them and as I said, it”s our duty to speak up to them when we think that the framework they”re talking about doesn”t meet electoral standards,&#34 Dujarric said. &#34When there is a contradiction on two different interpretations within one text, that would become an issue.&#34

The dispute came as officials began distributing the constitution to the public, less than two weeks before the vote. Some 5 million copies printed by the United Nations arrived in Iraq on Monday, and officials began passing the first ones out, said Laura Makdissi, a U.N. official in Baghdad.

A Sunni boycott of the Oct. 15 referendum would deeply undermine the legitimacy of a constitution that the United States had hoped would bring together the country”s disparate factions and erode support among Iraq”s Sunni Arab minority for the insurgency. Sunnis oppose the constitution, but U.S. officials are still trying to ensure they participate in the vote.