Canadian Prime Minister Stephen Harper is joining 27 other NATO leaders in Lisbon, Portugal this weekend, for two days of meetings that will include the first public discussion of the alliance's exit strategy for Afghanistan.

In light of Harper's recent decision to extend Canadian military operations in Afghanistan beyond the scheduled pullout next July, officials say he will be seeking assurances from Afghan President Hamid Karzai.

"I think the message that President Karzai will hear, given that we've been engaged in Afghanistan for a long time, is that we will remain engaged but we certainly expect the Afghans to do their share of the work," a senior Canadian government official said before Harper's departure.

"They will expect President Karzai to make a very strong commitment to the transition," the unnamed official told The Canadian Press. "They will also want to hear him on the transition leading to 2014, how that is actually unfolding and support that."

When asked to comment, Afghanistan's ambassador to Canada said Karzai expects no less.

"It goes without saying that without the Afghans doing their share, there will be no transition. It's absolutely predicated on that," Afghan envoy Jawed Ludin told CP, noting that the 2014 timeframe mirrors Karzai's own suggestion.

"His (Karzai's) ability and the ability of the Afghan government to be prepared to take over responsibility will also depend on the extent to which the international community supports the training and development efforts," Ludin said.

Karzai's relationships with his Western counterparts have been particularly strained since he said in an interview with the Washington Post last weekend that American-led forces should cease nighttime raids and other military operations in Afghanistan.

The commander of NATO-led forces in Afghanistan, U.S. Gen. David Petraeus, took Karzai's remarks as a direct rebuke of his mission.

But NATO Secretary General Anders Fogh Rasmussen said this week that he agreed with the "thrust" of the Afghan president comments, if not his frequent diplomatic faux pas.

"Of course, I can't say that I agree with everything President Karzai has stated on all issues, but we also have to accept that he is the elected president of the country, and of course, he can express his views as he wishes," Rasmussen said.

Harper confirmed last week that when Canada's 3,000 troops end their combat mission in July, it will deploy up to 950 troops and support staff for a training mission that will continue through March, 2014.

The U.S. is expected to announce in Lisbon this weekend that its own phased transition will complete by the end of that year.

Also on the agenda: NATO leaders are expected to reveal their strategy for continued operation in a world of cyber terror and rogue nuclear states.

Leaders of the 28 NATO member states will be joined by 20 other allies including Russian President Dmitry Medvedev for the talks Friday and Saurday.

Harper is attending the meetings accompanied by Foreign Affairs Minister Lawrence Cannon, Defence Minister Peter MacKay and his chief of defence staff, Gen. Walt Natynczyk.

With files from The Associated Press