Investigators of the police's National Fraud Investigation Unit will arrive at the prime minister's official residence in Jerusalem and present him with questions regarding the suspicions against him.
The key witness in the case, Jewish American philanthropist Morris Talansky, is expected to return to Israel soon in order to undergo a cross examination next Thursday by Olmert's lawyers, following his pre-trial deposition at the Jerusalem District Court in May.
The prime minister recently estimated in talks with Kadima activists that "this deposition will collapse in the cross examination."
Olmert is suspected of illicitly receiving funds before beginning his tenure as prime minister. According to the suspicions, he received envelopes containing cash money, believed to amount to hundreds of thousands of US dollars, for a long period of time.
Law enforcement officials have defined the offense as "bribery". The State Prosecutor's Office recently decided to speed up the investigation into the affair.
Talansky testified for seven hours at the Jerusalem District Court on May 28, and said he had provided the prime minister with cash envelopes and credit cards and paid for his flights and his stays at luxury hotels, in addition to a generous loan of hundreds of thousands of dollars.
The testimony caused a political turmoil in Israel. Defense Minister Ehud Barak urged Olmert to resign and Foreign Minister Tzipi Livni called for early primary elections in the Kadima party.