JERUSALEM (CNN) -- Authorities continue to investigate Israeli Prime Minister Ehud Olmert and a former top aide, and a court said Tuesday it may question a foreign national in connection with the probe.
Israeli Prime Minister Ehud Olmert is under investigation, but a court-imposed gag order is in place.
The case is under a strictly imposed court gag order, but the Jerusalem court identified the foreign national as a witness in the investigation. Olmert's attorneys and government representatives asked the court to depose the witness.
"There is nothing in this to attest that an indictment has been submitted against the respondents in the request -- Prime Minister Ehud Olmert and Ms. Shula Zaken," the court said.
Zaken, Olmert's top lieutenant for 30 years, was suspended as head of the prime minister's office last year amid allegations that she appointed cronies to Israel's Tax Authority.
The prosecution is expected to decide soon whether to charge her in connection with the tax authority case, according to the Israeli newspaper Haaretz.
Zaken has refused to cooperate with the investigation into Olmert. She has been placed under house arrest, the newspaper reported.
Police questioned the Israeli leader Friday for about an hour, and he said he fully cooperated.
According to Haaretz, it is the fifth investigation into Olmert since he became prime minister two years ago and "the latest in a longer string of probes to dog him during his three decades in politics."
Olmert has never been convicted of wrongdoing.
Olmert remains under investigation for purchasing a house in an upscale Jerusalem neighborhood. The then-Jerusalem mayor allegedly paid less-than-market value for the house and provided favors in return.
Israeli officials also are investigating an alleged $10 million business deal involving his former business partner. Olmert allegedly took part in the deal when he was minister of industry, trade and labor.
Officials also have investigated allegations that Olmert made appointments at the Small Business Authority on a political basis.
A yearlong probe into Olmert's role in the privatization of Israel's second largest bank wrapped up in November. No charges were filed against the prime minister.
Because of the gag order in the current investigation, it's unclear if the probe is connected to earlier ones.
Olmert has been dogged by dismal approval ratings since Israel's 2006 war with Hezbollah militants in Lebanon, which some analysts said failed to weaken the group either militarily or politically.
He also is under pressure from the United States, a key ally, to forge a peace deal with Palestinians by year's end. A weekend visit by U.S. Secretary of State Condoleezza Rice was overshadowed by media reports of the investigation. Watch Rice say a peace deal could be imminent »
President Bush is heading to Israel next week to mark the Jewish state's 60th anniversary.
Olmert's supporters said the investigations are a political move by opponents who want the Israeli leader out of office.
Olmert slammed media reports from last week saying that authorities are investigating bribery allegations in connection with the prime minister. Olmert on Sunday called the reports "a wave of rumors."
"It is obvious that by the nature of things in situations like this, rumors and hints and information from supposedly informed sources are thrown into the air about severe things, most of them malicious and wicked things," he said.
"I promise that once things are cleared by the authorities, things will be put in the right proportions, the right and accurate context, and that will put an end to the rumors." E-mail to a friend
CNN's Kevin Flower contributed to this report.