OTTAWA - Canadian soldiers and increased aid will be needed in Afghanistan for at least another two decades, says the head of UNICEF Canada.

Nigel Fisher says heated political debate in Parliament over the length of the Afghan mission is misguided.

"To me, we're just wasting energy to talk about an exit strategy now,'' he said in an interview Tuesday.

"What we should be doing is questioning why we're there, and coming up with a rationale that holds water and that the Canadian public could understand -- even if they don't agree.''

The government has done a poor job of publicly conveying the crucial role Canada can play to rebuild war-ravaged Afghanistan, Fisher said.

"It's when you give confused messages, or all we see is Canadian soldiers coming back in body bags, that we don't see the positive side of what they're doing.''

MPs should be discussing ways to refocus and increase aid in ways that the Afghan people -- and Canadian taxpayers -- can measure, he said.

These include an urgent need to help more Afghan women survive some of the highest maternal mortality rates in the world. Much more could also be done to provide books and other basics for Afghan schoolchildren, he said.

Afghans are risking their lives in the most unstable parts of the country to keep classes open, and yet lack the most basic teaching tools, Fisher said.

"If they're prepared to risk themselves, we should be prepared to support them.''

Canada plans to spend about $1.2 billion over 10 years in aid to Afghanistan by 2011.

Fisher said micro-credit programs to generate local income are among funding successes. But Canada's help would be more obviously effective for people on the ground if it were less "thinly spread'' among so many areas, he said.

Equipping schools and bolstering services for pre- and post-natal care would have an immediate impact with measurable results, Fisher said. He would like to see annual aid funding boosted to about $250 million, up from the $139 million spent in Afghanistan last year -- an increase he says Canada can well afford.

"We could do much more if there were more resources.''

A stable, prosperous Afghanistan could be a vital buffer against future attacks that would revisit the horrors of 9/11, Fisher suggested.

"Any failed state these days is a potential incubator for terrorism, extremism, whatever you like to call it.''

But such success will take "two decades'' or more and will require military might, he said.

"A strong, international military presence is needed now and probably for five years at least. To me, that's the floor and not the ceiling."

Opposition MPs have accused the Conservatives of plotting to extend Canada's military role well beyond its current commitment to the end of February 2009. They cite government plans to spend $650 million for up to 120 tanks, some of which won't be ready until mere months before the current mission is set to end.

Prime Minister Stephen Harper reaffirmed the February 2009 cut-off on Tuesday in the House of Commons. He also said his minority government would seek Parliament's support if it wished to extend the deployment.

"The fact of the matter is that this government, the United Nations and this Parliament believe this mission is important for the Afghan people, for the United Nations and for our national interests.

"I think while our men and women in uniform are there and in dangerous circumstances pursuing our interests, they deserve the support of all members of the House."