Iranians voted on Friday in a parliamentary election weighted in favour of conservative supporters of the Islamic Republic's clerical establishment.

Many reformist opponents of hardline President Mahmoud Ahmadinejad were barred from the race. But the new assembly might not give him an easy ride, even if conservatives dominate.

Polling stations closed at 11 p.m. (7:30 p.m. British time), five hours later than planned, to allow more people to cast ballots. Counting was to start at midnight, state media said.

Interior Minister Mostafa Pourmohammadi said some results would be announced on Saturday, but Tehran might take longer. He said turnout exceeded the 50 percent of four years ago, while another official said it topped 60 percent.

Some anti-Ahmadinejad politicians said their informal exit polls suggested the United Front, the most pro-government group of candidates, was doing well in Tehran. Conservatives held 26 of the capital's 30 seats in the outgoing assembly.

But even if conservative factions consolidate their grip on the 290-seat assembly, there are critics as well as supporters of Ahmadinejad in their ranks.

Some of his potential rivals in next year's presidential election say he has fuelled inflation. Others blame his fiery style for keeping Iran on a collision course with the U.N. Security Council, which this month imposed more sanctions on the Islamic Republic over its disputed nuclear programme.

Reformists favouring more political and social freedom had hoped to capitalise on public discontent about inflation, now at 19 percent. But the vetting process and a government crackdown on dissent muted their challenge. They may struggle to keep the 40 or so seats they had held in the previous parliament.

The United States, at odds with Iran since the 1979 Islamic revolution, criticised its foe's electoral process.

"In essence the results are cooked ... in the sense that the Iranian people were not able to vote for a full range of people," State Department spokesman Sean McCormack said.

The rising cost of living preoccupied most voters, whose country is the world's fourth-biggest oil producer.

"The economy is the issue. I will vote for those who can sew up the hole in my pocket," said Ali Mashallahi, a government employee with three children.

SHRUGGING OFF COMPLAINTS

Supreme Leader Ayatollah Ali Khamenei, who usually stays above the political fray, effectively endorsed Ahmadinejad in remarks published on Thursday and relayed in mobile phone text messages as voters went to the polls.

He said Iranians should consider "voting for those who can pave the way for the current government, which is active and willing to serve".

Shrugging off complaints that the system was stacked against reformists, Ahmadinejad said after voting: "Parliament belongs to the people and it should be a reflection of what they want."

Some Iranians were not convinced their votes would count.

"Ahmadinejad's supporters will win again, so why should I bother?" said Farnak, 25, a housewife out shopping.

Reformists, while arguing the election was unfair because many of their candidates were disqualified, had urged Iran's 44 million eligible voters to deny conservatives an easy victory.

Some of those queuing at the Haft-e Tir polling station at a Tehran mosque echoed that argument. "We have to support reformists. If we don't vote, their opponents will take more seats," said Mohammad Ziafati, 62, a retired teacher.

The poll may offer clues to Ahmadinejad's chances of re-election next year, though analysts say he will need to keep the support of Khamenei and other parts of the state apparatus.

Khamenei, not Ahmadinejad or parliament, has the last word on major policy issues such as the nuclear programme.

The president can rely on loyalists like Hassan Siavashi, 45. "It is my religious duty to vote. I pray God will help Ahmadinejad's group to win," he said before voting in Tehran.

Bibi Zahra, an elderly woman in a black chador, said she had put her trust in her son's choice. "I don't know who I was voting for, he filled in the form for me," she added.