Defence Minister Peter MacKay said Thursday NATO allies who are reluctant to lend help in Afghanistan should think about what will happen if Canadian forces are not replaced when they are expected to pull out in 2009.

"We understand the caveats, we understand the constitutional limitations, we understand the political volatility, but NATO cannot fail. This is a no-fail mission," he told reporters in Washington.

MacKay met with his U.S. counterpart, Defence Secretary Robert Gates, for the first time since he took over the portfolio in the cabinet shuffle last month.

His visit caps a series of whirlwind meetings with officials from England, Norway and the Netherlands.

During a meeting in Amsterdam on Wednesday, MacKay said NATO must do more to help in the dangerous southern part of Afghanistan.

Unless Parliament agrees unanimously to extend the mission, Canadian soldiers will pull out of Afghanistan in February, 2009. Currently, no NATO allies have stepped forward to take their place.

"I still hold up a fair bit of hope and optimism that they will recognize that if the job is not done in Afghanistan, if countries like Canada leave, the Taliban can follow them," MacKay said.

"These threats are not going to stay isolated. We know that Afghanistan was an incubator and an exporter of terror."

The concern is shared by Barnett Rubin, director of studies at the Center on International Cooperation at New York University.

"It means that there would be a very serious deterioration of security in the heartland of the Taliban," he told Â鶹´«Ã½. "It's quite possible that they will regain control of large swathes of territory in the south of Afghanistan."

International conference

Also Thursday, Liberal Leader Stephane Dion criticized the Conservative government's stance on Afghanistan, saying it was a mirror of the United States' policies.

Dion was attending a conference on Afghanistan held in Montreal this week. 

"The United States is our ally but not our model. This is a distinction this Conservative government has never understood," he told reporters.

When asked, Dion said he would end the combat mission in February, 2009, but keep the troops there to help rebuild.

"To answer in detail your question is not possible for the leader of the Opposition, is not possible today because we need to do that in concentration with our allies," he told CTV Montreal.

Omar Samad, Afghanistan's ambassador to Canada, also spoke at the conference in Montreal, saying the country's role and its sacrifices are a "positive influence," and asked again for Canada to stay past 2009.

"History has shown us that all nations that have been post-conflict have had to go through many years of rebuilding and Afghanistan is no exception," Samad said.

Pentagon talks

The Afghanistan mission was the primary focus of MacKay's hour-long meeting at the Pentagon.

After the meeting, MacKay told some NATO countries are assisting by sending equipment and helping with training and reconstruction, but that's not enough.

"We know that we have to have greater capacity in the Afghan National Army and Afghan National Police, so there are specific niche roles that countries that are not prepared to necessarily to come to Kandahar and RC South (Regional Command South) to play that type of assistance," MacKay said.

"We need people that are prepared, by all means, to come to RC South, to share in the heavy lifting."

He'll be lobbying NATO members to become more active in dangerous southern Afghanistan at informal talks in the Netherlands next month.