Afghan security forces clashed with suspected Taliban insurgents in southern Afghanistan, and a subsequent airstrike in the area left 35 militants dead, an Afghan official said Thursday.

The clash in southern Zabul province occurred as NATO military leaders met in Canada to ask for more resources for their fight in the volatile south.

Afghan security forces were ambushed and clashed with militants for about an hour in Zabul's Shahjoy district late Wednesday before an airstrike was called in on militants positions, said Ali Kheil, a spokesman for the Zabul governor.

Authorities recovered the bodies of 35 dead militants, Kheil said. There were no casualties among Afghan security forces.

U.S.-led coalition and NATO officials did not immediately comment on the attack.

• More coverage of the struggle for stability is available in FOXNews.com's Afghanistan Center.

Also Wednesday, two Canadian soldiers were killed and three wounded in a bomb explosion in the southern, said Col. Mike Cessford, deputy commander of the Canadian contingent in Afghanistan.

He did not disclose the exact location of the attack. Most of the Canadian troops serving in the NATO-led force in Afghanistan are based in the volatile southern province of Kandahar.

The blast occurred three days after six Canadian troops were killed in a roadside bomb explosion, also in the south. Those deaths were the single worst combat loss for Canada in Afghanistan.

Canada has lost 53 soldiers and one diplomat in Afghanistan since deploying to the country, according to the Canadian military.

There are some 2,500 Canadian troops in Afghanistan in the 36,000-strong NATO force.

As NATO pushes forward with its biggest ever anti-Taliban offensive in southern Afghanistan, U.S. Defense Secretary Robert Gates was in Canada Thursday to press allies to contribute additional forces, equipment and other resources in Afghanistan for that fight.

Gates was to meet with military leaders from Britain, Canada, Australia, the Netherlands, Denmark and Romania — all partners in southern Afghanistan.

NATO and the U.S. have made repeated calls for additional resources from allies, but have met resistance from some, including the French and Germans, who questioned the wisdom of sending more troops to Afghanistan.

Each year Taliban fighters have stepped up their attacks as the spring thaw began, but this year Gates said NATO should take the offensive and bring the fight first to the militants.

The initial phase of the assault began last month with Operation Achilles — sending more than 5,500 NATO and Afghan troops into opium-producing Helmand province to battle hardcore Taliban insurgents.

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