Prime Minister Stephen Harper won't bring up the issue of Guantanamo Bay prisoner Omar Khadr when U.S. President Barack Obama visits Ottawa next week, despite growing political pressure to act on the file, Harper's spokesman said.

"I don't anticipate either (leader) will raise it," spokesman Kory Teneycke told The Canadian Press on Wednesday.

Teneycke added that Kahdr's legal process is occurring in the U.S. and not in Canada. He added that Ottawa has yet to be asked by the U.S. to take back the Canadian-born detainee.

"There's not been a change in the U.S. position; there's not been a change in the Canadian position. We will respond to changes in the U.S. position if and when they occur," Teneycke said.

Those comments come despite a campaign by opposition MPs and Khadr's lawyers to repatriate the young prisoner.

Liberal Leader Michael Ignatieff, NDP Leader Jack Layton and Bloc Quebecois Leader Gilles Duceppe have written a letter to Harper and Obama calling on both governments "to act immediately" to release Khadr.

Khadr has been held at the U.S. military prison in Guantanamo Bay since he was wounded and captured by U.S. soldiers in a July 2002 firefight in Afghanistan. He has been charged with murder but has been imprisoned without trial for seven years.

The leaders say that because Khadr was 15 at the time of his arrest, Obama should acknowledge Khadr's status as a child soldier and "promptly release him."

"The interests of justice require acknowledgment of his status as a child soldier, his release from Guantanamo Bay, and his prompt return to Canada to be dealt with in accordance with Canadian law," the leaders write.

The opposition leaders say that Obama's planned visit to Canada on February 19 provides an ideal opportunity "to begin a constructive dialogue" on the Khadr file.

"Such action is imperative to the restoration and maintenance of both nations' commitment to the rule of law and to the implementation of the will of the majority of the Canadian people," their letter reads.

Harper has refused to pressure U.S. officials to send Khadr back to Canada, and rejects suggestions that Khadr, who is now 22, should be considered a child soldier.

Foreign Affairs Minister Lawrence Cannon has said that Ottawa would wait for a U.S. task force to review Khadr's case and decide whether he and other Guantanamo prisoners should be sent to their home countries, released or transferred to another U.S. prison.

On Wednesday morning, Liberal MP Bob Rae, Bloc Quebecois MP Paul Cr�te and NDP MP Paul Dewar held a news conference in Ottawa calling on the government to move forward with the Khadr case.

"He has been in Guantanamo prison for a long time," Rae said. "We believe his return to Canada is long overdue.

"It's in Canada's interest and it's in Mr. Khadr's interest to allow him to be reintegrated into ... Canadian society. If he is to face charges -- and that's an independent decision, not a political decision -- those charges should be considered in Canada under Canadian law."

Now that Obama has ordered the Guantanamo prison closed within a year, Dewar said it is time for Canada to take action on the Khadr file.

"We seem to have a government that's in deep denial at a time when in Washington the writing is being put on the wall for Canada," said Dewar.

"Guantanamo's going to be closed. Guess what happens next? Mr. Khadr has to go somewhere. I don't think Mr. Obama really cares to have him stay there."

Khadr's lawyers say their client would be willing to face prosecution in Canada and have presented Harper with a transition proposal if the United States sent him home, in which they suggest a "transition period" away from his family under the guidance of an expert team.

One of Khadr's lawyers, Dennis Edney, says his team is willing to alter the plan and do whatever it takes to repatriate their client.