Canadian Prime Minister Stephen Harper and U.S. President-elect Barack Obama on Thursday pledged to maintain and improve the strong U.S.- Canadian alliance.

The two had "a warm exchange" during a phone conversation as Harper called to congratulate the U.S. Democrat on his election Tuesday, according to a statement from the Canadian prime minister's office.

"In a warm exchange, the two leaders emphasized that there could be no closer friends and allies and vowed to maintain and further build upon this strong relationship," the statement said.

The two leaders also touched on the upcoming G20 summit in Washington that will discuss the international financial meltdown, the statement said.

Earlier Thursday, Harper pledged to work in full collaboration with the United States on such issues as environment and energy, the economy and the financial crisis, and international peace and security, particularly Afghanistan.

"For Canada, our most important international relationship is always with the United States," Harper told reporters in Toronto after a meeting with the country's top economists.

(Xinhua News Agency November 7, 2008)