KANDAHAR, Afghanistan - A scouting party from the NATO unit that could replace Canadian troops in Kandahar will be touring the area over the next few days.

Planning for the departure of Task Force Kandahar is underway and a proposal on how the transition will take place is still being finalized, a senior U.S. officer with the alliance's southern headquarters said Tuesday.

The Canadians "are in a critical location," said the officer, who spoke on condition of anonymity because he was authorized to discuss the situation on background only.

"We've got to make sure that area is still covered, and covered well."

The roughly 3,000 Canadian troops currently in theatre have brought "a significant capability" to the region, and when they go it "will be a significant concern to us," the officer said during a briefing at ISAF's Regional Command South headquarters.

The military official would not identify the incoming NATO unit, other than to say it had been in Afghanistan before and was "scheduled to come in the springtime period as part of a normal rotation of forces."

That means it is most likely American.

Once encompassing the whole of the province, the Canadian area of operation has been steadily shrinking, and now includes only three volatile districts south and east of Kandahar city -- Panjwaii, Dand and Daman.

Canadian military officials were not available to comment on the tour, which kicks off as Canada's defence and foreign affairs ministers unveil the plan for the army's transition to a training mission, which will keep troops in the war-ravaged country until 2014.

Canada will keep up to 950 "non-combat" troops and support staff in the Kabul area for a training and humanitarian aid mission after the current combat role ends in July, Foreign Affairs Minister Lawrence Cannon said Tuesday.

Defence Minister Peter MacKay said the troops would not go out on missions with their trainees. He said the new mission will cost the military up to $500 million a year. The move will cost $85 million.

The government will spend another $100 million a year over three years on development and aid.

Documents obtained by The Canadian Press under access to information laws show military planners have long been skeptical about Prime Minister Stephen Harper's pledge to pull Canadian soldiers out of Afghanistan entirely by 2011.

"It was recognized that a residual CF elements may remain in Afghanistan in a non-combat role post-2011," said a mission analysis briefing for the country's Ottawa-based overseas commander, Lt.-Gen. Marc Lessard.

It urged planners to be flexible because the drawdown to "zero" forces might not happen.

"What does zero mean?" said one slide presentation, which went on to joke that at CEFCOM, Canada's central military command in Ottawa, "there is some thought that zero is an imaginary number."

The report went on to note the "uncertain" planning climate and that "zero may not mean zero."

Nonetheless, in a recent interview with The Canadian Press, Lessard said he was instructed by the country's top military commander to do "no planning for a follow-on mission."

The army is now trying to figure out how to deploy up to 950 trainers and support staff for the new mission.

The American officer in Kandahar said no final decision has been made on how the gap will be filled in eastern Panjwaii district and in the area south of Kandahar city when Canada ceases combat operations next summer.

"Internally, if it's left to us, we'll make some adjustments and we're already starting to think through some of the 'be prepared' missions," the officer said.

The final call on where the unit will go will most likely be made by NATO's headquarters in Afghanistan. Another possibility is that the Canadian contingent could be replaced by Afghan troops.

The unit touring the Canadian stretch of the battlefield will also check out a second area of operation as part of contingency planning.

It is an awkward transition for Canadians who are used to running the show in Kandahar province, which has been flooded with upwards of 15,000 U.S. reinforcements over the last year.

The CEFCOM analysis noted the Taliban propaganda machine was hammering away on locals about the Canadians, "taking advantage of our planned withdrawal."

The army has to pay particular attention in the villages where it's been operating to reassure those people the Canadian troops have been dealing with, said the report.

The mission between now and July 2011 was to "remain relevant to Afghan population, NATO/ISAF partners, (and) WoG (without guns) partners," such as aid groups, until operations ceased.

The Americans have been leading a major combat operation in western Panjwaii for the last few weeks, while Canadian and Afghan units hold eastern regions of the district. It is all part of NATO's major push through Kandahar, which started last summer.

U.S. troops have conducted dozens of airborne assaults in the last few weeks throughout the vast swath of parched farmland.

The Panjwaii has a long and violent history. During the 1980s, the Soviets drove most of the 30,000 residents out of their homes after facing repeated ambushes and bombings.

With the end of the occupation most residents never returned and the Taliban have since used the abandoned compounds as bomb-making factories.