The top United Nations envoy in Iraq urged election officials Wednesday to release the results of this week's historic vote as quickly as possible, saying Iraqis "have the right to know as soon as possible what is the outcome of their choice."

The call by U.N. diplomat Ad Melkert came as Iraqi election officials furiously counted ballot tallies in Sunday's election that appeared to be coming down to a contest between Prime Minister Nouri al-Maliki, former premier Ayad Allawi and a coalition of conservative Shiites.

Meeting with vote-counters at the Independent High Electoral Commission in Baghdad, Melkert said the first results were likely to be released Thursday. He cited a "very complicated process" for the time it was taking.

"Now we hope, that as soon as possible, preliminary results can be made public because Iraqis have the right to know as soon as possible what is the outcome of their choice of the Election Day," Melkert told reporters at the commission headquarters.

Election commission officials also backed off an earlier announcement that preliminary results would be released Wednesday night. A senior member of the panel, Qassim al-Aboudi, said the first results likely would come Thursday.

Commission chairman Faraj al-Haidari said vote counters were entering results into the computer and that updates on that process might be ready on Wednesday.

The results of the parliamentary elections will largely set the course for Iraq as the U.S. military prepares to leave at the end of 2011 — eight years after the invasion.

The election was only the country's second for a full parliamentary term, and it attracted 62 percent of about 19 million eligible voters, according to the nation's election commission. The last legislative election, in December 2005, attracted roughly 76 percent of eligible voters.

With ballots still being counted, officials from al-Maliki's State of Law coalition and the rival Iraqiya, led by Allawi, claimed to be ahead. Election officials across the country also reported a strong showing by the religious Shiite Iraqi National Alliance, which aims to cement Shiite dominance of Iraq.

Underscoring concerns that a dispute over the vote results could delay the new government and give rise to instability and violence, Melkert called the vote count "an honest counting."

"That is why it is very important that the announcement of the preliminary results will be accepted by all," he said. "An election always leads to relative winners and relative losers, but all candidates, whether winning or losing, make up the value of the elections."