HALIFAX — Defence Minister Peter MacKay says Canadian troops are not in Afghanistan to guard a new natural gas pipeline being built through the southern part of the country.

MacKay told a Halifax radio talk show on Wednesday that Canada has to let Afghanistan map its own future. He said fears that Canadian troops may end up paying a hefty price to protect the U.S.-backed project from insurgents are unfounded.

"We have to decide what role, if any, we'll play," said MacKay.

"We are not there specifically to protect a pipeline across Afghanistan."

The minister said it's incidental to the role Canadians are already playing.

"We're going to try and prevent chaos, if the Taliban are attacking certain places in the country or certain projects, then yes we will play a role."

The proposed pipeline would run through Turkmenistan, Afghanistan, Pakistan and India.

Construction is scheduled to start in 2010, one year before Canada's Afghan mission is expected to end.

MacKay said Canada's primary purpose is to help the people of Afghanistan help themselves.

"Our primary purpose there is to build that country to the point where they can walk on their own and then we're coming home."