Charles Jenkins, 64, accused of abandoning his Army post in 1965 and defecting to North Korea, came to Japan earlier this month for medical treatment.
National broadcaster NHK and Kyodo News service reported Monday that a meeting this week between Jenkins and counsel affiliated with the U.S. military was being worked out.
The reports came less than a week after the U.S. military answered a Japanese government request for information on the military's independent legal counsel system and court-martial procedure, said Col. Victor Warzinski, spokesman for the U.S. military.
NHK said the United States and Japan were negotiating a meeting that could take place before the end of the week. Such legal counsel would be the military equivalent of a court-appointed lawyer.
The broadcaster, however, said the move did not necessarily mean Jenkins had decided to attempt a plea bargain.
The reports cited unidentified officials. Officials with the U.S. Embassy, the U.S. military and the Japanese Foreign Ministry said they could not confirm the reports.
An influential ruling party lawmaker backed such an approach later Monday.
"I think it would be good for Mr. Jenkins, with the help of a lawyer, to face up to the current situation and speak with American judicial authorities," Shinzo Abe, a close aide to Prime Minister Junichiro Koizumi, said in a speech to other ruling party officials.
The United States has not yet requested custody of Jenkins, citing humanitarian concerns over his health, though Washington has insisted that it still plans to pursue a case against him.
Jenkins' Japanese doctors, however, announced last week that he did not suffer from any serious illness, and the focus has shifted to how he would handle his legal troubles.
Chief Cabinet Secretary Hiroyuki Hosoda said Jenkins had not yet told officials what his legal plans were.
"So far, we have not heard anything from Mr. Jenkins himself about what exactly he wishes to do," Hosoda said. "Nothing is concrete at this moment."
The Japanese government is pushing for U.S. leniency with Jenkins so he can live together in Japan with his Japanese wife, Hitomi Soga.
Soga was kidnapped by North Korean agents in 1978 and met and married Jenkins in the communist state. Soga, however, was allowed to return alone to Japan in 2002, and her efforts to reunite her family — the couple has two daughters — have won deep sympathy here.
Speculation has been rising in Japan that Jenkins could attempt to strike a plea bargain with the U.S. military by pleading guilty to some of the charges against him in return for reduced punishment.
Some also believe Jenkins could win leniency by providing U.S. officials with information about reclusive North Korea.
The Japanese government had asked the U.S. military about information on its justice system and its equivalent of court-appointed attorneys, said Warzinski.
Warzinski, however, said such counsel would work directly with the defendant and he would have no information about whether a meeting with Jenkins was being arranged.
By Joseph Coleman