Canada's new ambassador to the U.S. begins his duties in Washington, D.C., on Monday.

One of the challenges that former Manitoba premier Gary Doer must deal with is the U.S. "Buy American" policy.

The Canadian Manufacturers and Exporters Association estimates Canada is being excluded from competing on about $290 billion in American stimulus projects.

American labour unions are apparently opposed to a Canadian exemption for fear it will affect U.S. jobs. Doer said he's friendly with some U.S. labour officials and hopes it will be another opportunity to exert influence on American policy.

Trade Minister Stockwell Day is due to meet U.S. Trade Representative Ron Kirk in Dallas on Monday to discuss the issue.

Doer said his contacts in the labour movement on both sides of the border may come in handy in persuading the U.S. government to give concessions to Canada.

The longtime premier announced Aug. 27 that he would be stepping down. The following day, he was introduced in Ottawa by Prime Minister Stephen Harper as Canada's next ambassador to the United States.

On Sunday, Doer handed over the premier's office to his successor, Greg Selinger.

Selinger, who has served as his finance minister under Doer's NDP government since 1999, was elected to replace the outgoing premier at the NDP's leadership convention in Winnipeg on Saturday, defeating his rival, Steve Ashton, by a large margin.

With files from The Canadian Press