Stephen Harper

President Bush will spend part of his 60th birthday Thursday holding talks with Canadian Prime Minister Stephen Harper at the White House.

This is Mr. Harper's first official visit to Washington since his Conservative party won parliamentary elections in January. The two leaders are expected to discuss Canada's participation in in the U.S.-led military operation in Afghanistan and the nuclear standoffs with Iran and North Korea.

The traditionally close ties between Canada and the United States were strained under Canada's previous government, which opposed the U.S. invasion of Iraq.

Relations appear to have improved somewhat under Mr. Harper's Conservative government.

Both sides recently reached a deal to resolve a 20-year dispute over softwood lumber subsidies.