Prime Minister Stephen Harper is continuing his string of almost monthly meetings with U.S. President Barack Obama.

Harper will see Obama this weekend in Mexico for the North American Leaders' Summit and then he will travel to the U.S twice in September for meetings.

Today, the prime minister's staff announced Harper would be going to the White House on Sept. 16 for what's called a working visit, similar to the one Obama made here back in February.

James Fitz-Morris

This will be Harper's second official visit to Washington, although the first since Obama took office.

The formal agenda hasn't been set, but officials say the two leaders are likely to cover such topics as border security, energy and the environment, as well as the most important, to them, trade and the economy.

This meeting will also allow Harper to get a preview of what Obama has planned when he hosts the G20 summit of the world's 20 largest economies the following week in Pittsburgh to discuss the global economic crisis.

Since January, when Obama took office, Harper has already met with the U.S. president six times either one on one or at international summits, not including the three scheduled between now and the end of September.

This sharp rise in meetings between the Canadian and American leaders has little to do with any change in the Canadian approach, officials say, and almost everything to do with the change of leadership in the U.S.

— James Fitz-Morris