Washington (CNN) -- Secretary of State Hillary Clinton is reaching out to Canadian officials this week as part of a U.S. effort to resolve the case of Guantanamo detainee Omar Khadr, according to two sources.
One source close to the negotiations said, "Khadr will have to decide" whether to sign onto a tentative deal negotiated by prosecution and defense lawyers. That arrangement calls for Khadr to be sentenced to eight years--- one year to be served in U.S. custody and seven years to be served in Canadian custody.
Canadian government officials are closely involved in the negotiations, the source said.
This source said it's expected the U.S. and Canadian governments will exchange diplomatic notes on the subject Friday.
A State Department official says Clinton is scheduled to discuss the matter with Canada's foreign minister Wednesday night.
According to the source close to the negotiations, the key is whether 24- year-old Khadr will agree to a plea deal. The source said he has been discussing the matter with his Canadian civilian lawyer, Dennis Edney. According to media reports, Khadr indicated at a July pretrial hearing that he had rejected an earlier plea offer.
According to the source, if a plea agreement is hammered out this week there would be a plea inquiry proceeding at Guantanamo next week that would last approximately one week. During that process, the terms of the plea would be outlined, and prosecutors and defense lawyers then would present evidence and make arguments on aggravating and mitigating factors that should affect Khadr's sentence.
Khadr was 15 when he allegedly threw a grenade during a 2002 firefight in Afghanistan that resulted in the death of Army Sgt. 1st Class Christopher Speer. If convicted, Khadr would face a maximum life sentence.
The military commission began in August but was stopped in the first week due to the illness of Khadr's military lawyer. It's the first such commission conducted during the Obama administration.
CNN's Elise Labott and Jill Dougherty contributed to this report