KUWAIT - Kuwaitis voted on Saturday in a divisive parliamentary election held under new polling rules that triggered an opposition boycott of the ballot and mass protests.

The election is the second this year in the oil-rich Gulf Arab state, where a series of assemblies have collapsed due to a power struggle between elected MPs and the cabinet.

Tens of thousands marched on Friday in what organisers said was the largest protest in Kuwaiti history, to urge people to shun the ballot box in protest at a rule change they say will skew the outcome in favour of pro-government candidates.

The ruling emir, Sheikh Sabah al-Ahmad al-Sabah, used emergency powers in October to cut the number of votes per citizen to one from four, saying his decree would fix a flawed system and ensure national unity.

The opposition says the new one-vote system will prevent its candidates winning the majority they had in the last vote.

In the past, its candidates have called on supporters to cast their additional ballots for allies. They say such informal affiliations are crucial due to a ban on political parties.

"The old system was unfair for people in some areas of Kuwait," 28-year-old Dalal al-Aboud said at a voting station in a suburb on the edge of Kuwait City.

"I think it will be better if we try this new method, then we judge if it is fair or not."

Polls opened at 8 am (0500 GMT). About 423,000 Kuwaitis are eligible to cast ballots to choose the 50 members of parliament.

Turnout crucial

Officials in polling stations in several districts said turnout appeared lighter than usual, but final figures would only be ready later in the day. Polls close at 8 pm (1700 GMT) and results may come around three hours later, officials said.

Opposition figures, who include Islamist, tribal and liberal former lawmakers, have refused to stand.

Information Minister Sheikh Mohammad al-Mubarak al-Sabah said there was a "significant and positive" voter turnout in the second district, which comprises the capital and nearby areas. ?

The opposition tends to dominate voting in poorer districts furthest from the capital.

Near a polling station in the south of the country, where tribal candidates have polled strongly in the past, Ahmed al-Azemi said he would not vote because his tribe was boycotting.

"The Azemi family, we are against the election," he said. "The new parliament will last only a month. A National Assembly without the opposition is useless."

Around him older men sat drinking tea and arguing about the boycott. Asked who had voted, three of the 10 raised their hands, to shouts from the others.

"If the turnout is lower than 50 percent then you could say the boycott is successful," said Ghanem al-Najjar, professor of political science at Kuwait University.

Turnout in the past three elections was around 60 percent.

Kuwait, a US ally, has the most open political system among the Gulf Arab states with a parliament that has legislative powers and the ability to scrutinize ministers.

But the emir's Al-Sabah family, which has ruled Kuwait for 250 years, holds the main portfolios in the cabinet and Sheikh Sabah has the final say in state matters.

"His highness the emir is responsible for the country and knows best how to maintain its stability," Interior Minister Sheikh Ahmad al-Hamoud al-Sabah said.

"Kuwait was, still is and will continue to be a beacon in the Arab world when it comes to the transparency and impartiality of elections," he said on state news agency KUNA.

Female voters and candidates

University professor Alia Shuaib said women, who received the right to vote in 2005, were still finding it an uplifting experience to cast their ballots.

"I believe it is my duty as a woman and as a Kuwaiti national to vote," she said.

"It is a pleasure to get up, dress, get my papers and vote. It is breathtaking," the 45-year-old said.

"I believe every person should vote and put the right people in parliament. We want educated people, the best."

There are 14 female candidates out of a total of 302. The last parliament contained no female MPs.

The opposition won around two-thirds of the National Assembly in February and formed a bloc that put pressure on the government, forcing two ministers from office.

That parliament was dissolved after a June court ruling, the latest stage in a standoff which has stalled investment and economic reforms.