Jerusalem - Israeli police questioned Prime Minister Ehud Olmert for a fifth time time Friday over two alleged corruption affairs in which he is suspected of being implicated.

The questioning lasted for three hours, an hour longer than scheduled, after Olmert requested it be extended, media reports said.

Israel Radio reported that the questioning focused on allegations the premier double- and even triple-billed sponsors for overseas visits, and used the extra money to pay for trips for his family.

He was also questioned on allegations that in the years before he became prime minister he received hundreds of thousands of dollars, most of it via envelopes full of cash, from US-Jewish fundraiser Morris Talansky.

Olmert has denied the accusations, and although he admitted receiving funds in what has become known as "the money envelopes" affair, denies the sums mentioned, and insists it was legitimate reimbursements for food and accommodation.

Israel Radio last week quoted a "police source" as saying that he believed that the investigation into both affairs would end in a few weeks and a recommendation would be made to indict the prime minister.

On Thursday night, however, police said it would be "irresponsible" to say whether Friday's session would be the last interrogation Olmert would undergo.

"The same is true regarding an indictment. When we're done, we'll announce it," The Jerusalem Post daily quoted a police spokesman as saying.

Earlier this week, Israel's High Court rejected a petition by an Israeli journalist, who asked the court to order the attorney-general to instruct the government to suspend the premier until the outcome of the investigations were known.

The court did however say that the attorney-general did have the authority to order the suspension of the premier and such a move would have to be considered if the investigations dragged on.

A former head of the country's National Fraud Unit claimed Thursday that Olmert was "playing for time" and using constant "evasive techniques." Olmert's spokesman dismissed the claim as "nonsense."

The ongoing investigations have further eroded Olmert's already- low popularity, and the beleaguered premier said last week that he intends stepping down from the premiership after his Kadima party chooses a new leader in primaries on September 17.

Announcing his intentions in a televised appearance, he also slammed the conduct of the investigations against him, saying that while he was proud to live in a country "where the prime minister can be investigated like any other citizen" he had "been denied the elementary right to the presumption of innocence."

Olmert's office is currently involved in a public spat with the police and the state prosecutor's office regarding leaks from the investigations against him.

Accounts of police interrogations of witnesses and others involved in the alleged scandals have often appeared in the media within a very short time of their having taken place.

The two cases over which Olmert was questioned Friday came to light only in recent months, and are the latest to beset the premier.

He is also suspected of buying a house in an upscale Jerusalem neighbourhood, at a price significantly below the market value, in return for helping the building contractor receive construction permits from the Jerusalem authorities.

There are also suspicions that, while trade and industry minister, Olmert pushed for a friend and former business partner to receive favourable treatment from the ministry's investment centre, and that he acted improperly by appointing political cronies to senior positions in the ministry's Small Business Authority.

In addition, allegations have surfaced that while finance minister Olmert intervened in the sale of Israel's largest bank to the benefit of two business associates. The allegataions however did not lead to an indictment.

Olmert became prime minister in March 2006, after he led the Kadima party to victory in Israel's Knesset parliamentary elections. His parliamentary career stretches back to 1974. As a novice legislator he made a name for himself by battling organized crime. (dpa)