By Opheera McDoom
KHARTOUM (Reuters) - Sudan's first open elections in 24 years fell short of international standards, international observers said on Saturday, the first authoritative judgments on the polls tainted by a wave of boycotts.

Official results of the presidential and legislative ballots, which had been intended to turn Sudan into a democratic state after decades of civil war, are due on Tuesday.

"These elections have struggled to reach international standards. They have not reached them all," the head of the European Union observer mission in Sudan, Veronique de Keyser, told reporters.

"It is apparent that the elections will fall short of meeting international standards and Sudan's obligations for genuine elections in many respects," said a statement from the U.S. Carter Centre, the only long-term observers of the polls.

The preliminary statements will be a blow to President Omar Hassan al-Bashir who, analysts say, is looking for an internationally recognised win to legitimise his rule and fend off International Criminal Court charges that he masterminded war crimes in Sudan's western Darfur region.

But the few opposition political parties which entered the elections also said they would never recognise the results.

"Even if we win one seat, and it looks like we won't even get one, we will never take it," said opposition Islamist Hassan al-Turabi, adding his party totally rejected the results.

"Now they went straight to the ballots and took them and exchanged them," he said, adding their monitors had caught some officials in the act of fraud.

INTERNATIONAL STANDARDS
The elections were set up under a 2005 peace deal that ended more than two decades of north-south war in the oil producing state and also promised southerners a 2011 referendum on whether they should split off and become an independent country.

A member of Sudan's National Elections Commission defended the election, saying it was not surprising there had been problems given the country's war-torn history.

"We cannot be expected to meet international standards. We are a country just emerging from the war with very little electoral experience , We have tried our best as a commission," Philister Baya Lowiri told Reuters.

De Keyser said there had been "significant deficiencies" including logistical problems, intimidation and irregularities.

She said there had been a small opening of political space with the opposition parties free to voice complaints, but said it was important that trend continued.

Both missions praised the patience and enthusiasm of voters and polling staff. Overall turnout would be around 60 percent, De Keyser said.

The elections as a whole were marred by complexity and confusion, and dominated by the ruling parties in the north and south, the EU's preliminary statement said.

A separate mission from the European Parliament echoed many of the concerns but said the polls were still a step forward in the 2005 peace process.

"They enabled an unprecedented political debate in a war-torn country," MEP Ana Gomes said.

The European Union deployed around 140 observers but pulled its team out of Darfur, the site of a seven-year civil conflict, saying safety concerns were limiting its movements.

Around 70 observers from the Carter Centre, led by former U.S. President Jimmy Carter, watched the vote.

(Additional reporting and writing by Andrew Heavens; Editing by Jon Hemming)