Federal prosecutors have agreed to drop four of the five criminal charges against an Indian national accused of attempting to extort $35,000 from Gov. Linda Lingle's former chief of staff, Bob Awana.

Pamela Byrne, attorney for Rajdatta Patkar, said yesterday that she is in the process of finalizing a plea agreement in which Patkar will plead guilty to one of the five extortion charges.

Byrne, a federal assistant public defender, said both sides are working on the wording of the agreement and amount of restitution to be paid.

Federal prosecutors declined comment yesterday.

The proposed plea agreement comes as Awana resigned last week as Lingle's chief of staff after details of the case were coming to light.

A March 2006 federal grand jury indictment alleged Patkar, a 44-year-old Indian national now living in Tokyo, attempted to extort $35,000 from Awana in 2005.

The indictment did not provide details of the alleged extortion attempt, but people familiar with the investigation said Patkar allegedly threatened to expose an extra-marital affair Awana had with a woman in the Philippines.

Patkar learned of the affair after finding e-mails Awana allegedly sent to the woman, the people said. The sources declined to be named, citing an ongoing criminal investigation.

Patkar previously had pleaded not guilty to the federal charges.

A hearing on a change of plea was scheduled for this morning before U.S. District Judge Michael Seabright, but the hearing was postponed until July 10.

According to Byrne, the remaining extortion count has a maximum sentence of about two years in prison. But Patkar will likely be credited for time already served in prison.

Patkar has been under custody at the Federal Detention Center near Honolulu International Airport since March. He also was under custody for several months in Japan while awaiting his extradition to Hawai'i, Byrne said.

The plea agreement has no bearing on a separate federal public corruption into a lucrative contract to operate a landfill in Saipan.

Awana, who has denied wrongdoing in the case, recently told The Advertiser that he was questioned by federal investigators.

Awana owns a 16 percent stake in the Saipan venture, which was awarded a five-year, $9.9 million contract by Saipan's Republican governor in 2002 to operate a new landfill in Saipan. But the contract was canceled last year by Saipan's current governor.

Reach Rick Daysog at rdaysog@honoluluadvertiser.com.