KABUL - The Afghan parliament on Saturday approved the defense, finance and interior ministers chosen by President Hamid Karzai, but rejected Ismail Khan for the powerful post of energy minister, and four other nominees.

Cabinet approvals are one of the few areas where parliamentary deputies have genuine power to hold the executive branch to account.

At a time when security and corruption problems are worsening dramatically, they have been exercising that influence, quizzing ministers for over a week on past policy and future plans and now rejecting a clutch of Karzai's choices.

Parliament stayed open for at least three extra hours to finish voting for the ministers, because a complicated secret ballot process that began early in the morning ran on all day.

The Yes and No votes for each of 24 ministers were being counted out individually to parliament, meaning the session was likely to run on late into the evening, but the speaker promised it would be finished on Saturday.

Karzai's nominations for cabinet keep many of the key ministers in post since before the presidential election in the autumn. However, he has not chosen a candidate for the key post of foreign minister, or explained why not.

Many of his Western backers are satisfied to see technocrats stay in position, but critics say the president is recycling old names at a time when the country needs new ideas.

The highest-profile scalp claimed by parliament was Ismail Khan, a renowned anti-Soviet guerrilla leader and anti-Taliban commander who was also energy minister in the last cabinet.

He is unpopular with some because of his role in an era when Afghanistan was split by civil war.

Khan received two more votes in his favor than against, but blank and spoiled votes tipped the balance against him in a system that requires candidates to get over half of votes cast, said the speaker of the house, Mohammad Younus Qanuni.

SECRET BALLOT?

The procedure was briefly held up when some MPs objected to the secret ballots, saying secret deals might be cut if representatives did not have to answer to voters for their choices.

There is a lot of wheeling and dealing behind the scenes, said parliamentarian Dawood Sultanzoy, from the province of Ghazni, southwest of the capital.

I hope that the representatives will vote based on their consciences, based on the needs of the country.

Some Western diplomats said the retention of top ministers reflected the difficulty Karzai faces in recruiting people who are qualified to take on big portfolios.

He appears to have refrained from giving top jobs to the most powerful former warlords who threw their weight behind his election campaign, with the exception of Khan. But they could yet make gains when nominees for deputy ministers or regional governors are announced.

(Writing by Emma Graham-Harrison; Editing by Kevin Liffey)