JERUSALEM — Prime Minister Olmert, who is the subject of strong public criticism over the war with Hezbollah, is to be investigated for an alleged property deal.

A spokesman for the Israeli state comptroller, Micha Lindenstrauss, said Mr. Olmert would be questioned concerning allegations that he was given a huge discount on an apartment in Jerusalem in exchange for manipulating the city’s planning laws.

“The examination was begun several months ago and has yet to conclude,” the spokesman said. “We have collected documents and testimony but have not yet addressed the prime minister. Any person investigated by this office has the right to explain themselves, and the final report will not be complete until the prime minister has been given that opportunity.”

Mr. Olmert’s office declined to comment on the allegations.

They first surfaced on an Israeli news Web site and have been picked up by the mainstream Israeli press.

It is alleged that Mr. Olmert was allowed to buy a garden flat two years ago for $1.2 million even though the market price at time was $1.8 million.

The state comptroller will look into whether Mr. Olmert was being paid back by the property developer for using influence to allow the building containing the apartment to be redeveloped in spite of planning restrictions.

The former mayor of Jerusalem who led the centrist Kadima party to victory in March’s general election, Mr. Olmert has seen his personal approval figures slide dramatically since the war with Hezbollah began.

The property deal allegation is the not the first time he has been accused of corruption. An earlier claim was investigated and dismissed by the state comptroller.

A recent report by the World Bank showed that Israel is regarded as the second most corrupt country in the West after Italy.