By David Lewis and Adama Diarra
BAMAKO (Reuters) - Former Malian Prime Minister Ibrahim Boubacar Keita holds a comfortable lead and could win an outright first-round victory in the West African nation's high-stakes presidential election, the minister of territorial administration said on Tuesday.
Keita's rivals immediately rejected the partial results, calling for the minister, who is in charge of the elections, to resign and an international commission to be established to tally the vote, which they said must go to a second round.
Voters turned out in large numbers across Mali on Sunday, eager for a fresh start after a March 2012 coup allowed separatist and al Qaeda-linked rebels to seize the desert north last year. It took an offensive by thousands of French troops in January to scatter them into the desert and mountains.
Voting was peaceful and observer missions have praised the polls, but tensions were rising as announcement of results neared.
"There is one candidate, Ibrahim Boubacar Keita, who has a wide margin compared with the other candidates," Colonel Moussa Sinko Coulibaly, the minister of territorial administration, told journalists in the capital, Bamako.
"If maintained, (it means) there will not be a need for a second round," he said. The results represented a third of ballots cast from constituencies across the country, he said.
Coulibaly repeatedly refused journalists' requests for exact numbers. He said the results had been certified by the elections commission.
Amadou Koita, spokesman for ex-Finance Minister Soumaila Cisse, who Coulibaly said was currently in second place, called the announcement "scandalous" and questioned why the minister refused to give figures to back up his statement.
"We quite simply reject these trends that were announced by the minister. We call on the minister to resign and an international commission ... to be set up to count the vote."
Koita questioned how the minister could give a projection based on one-third of votes when he said the commission that is made up of representatives from all camps and is tasked with collating results had only counted 12 percent of votes so far.
Minutes after the results were announced, cars and motorcycles on the streets of Bamako honked their horns and Keita's supporters outside his house chanted "IBK" "IBK" "IBK," the initials he is universally known by.
Cisse and two other of Keita's rivals - Modibo Sidibe, a former prime minister, and Dramane Dembele, the candidate of Mali's biggest party - came together on Monday to complain about the process.
Their FDR coalition, which was initially set up to counter last year's coup, complained that hundreds of thousands of people had been excluded from the vote due to technical shortcomings.
Members of the FDR coalition have claimed that world powers led by France, which pushed for the vote to be held despite concerns over Mali's readiness, favored Keita in the process.
Cisse said he would challenge the results if Keita is announced winner in one round.
"It is up to Mr. Cisse to prove what he claims and to use the legal existing channels for his claim. The imperfections will affect the winners as well as the losers," Louis Michel, the European Union's chief observer to the Mali mission, said on Tuesday.
"In my opinion, as of today, the problems that we have been told about will not have an impact on the legitimacy of the process," he told Reuters.
Average turnout was tallied so far at 53.3 percent, well above Mali's record high of 40 percent, Coulibaly said. Final results could be ready on Wednesday.
Whoever wins the election will have to push through national reconciliation efforts and conclude peace talks with Tuareg separatist rebels who allowed the vote to take place but are still armed in remote corners of Mali's desert north.
They will also oversee a 3 billion euro ($3.98 billion) plan proposed by donors to rebuild the nation and kick-start the economy.
(Reporting by David Lewis and Adama Diarra; Additional reporting by Tiemoko Diallo; Writing by David Lewis and Joe Bavier; Editing by Eric Beech)