Action - not rhetoric - will determine Canada's success in global affairs, declared Prime Minister Harper during a speech at one of the world's most influential foreign policy think tanks.

Speaking in New York before an audience at the Council on Foreign Relations, the publisher of the internationally renowned journal "Foreign Affairs," Harper said Canada must use its middle power status to lead, not lecture.

"Success demands governments who are willing to assume responsibilities, seek practical, do-able solutions to problems, and who have a voice and influence in global affairs because they lead, not by lecturing, but by example," Harper said.

Harper claimed numerous examples of Canada's influence on the world stage, including its roles in Afghanistan and climate change.

Harper cited the fact that Canada has just lost its 71st soldier in Afghanistan to show that there can be little doubt about Canada's contribution to fighting terrorism.

He said the Canadian presence in Afghanistan is "noble and necessary. (It is) a cause completely consistent with our country's proud history of supporting international action to fight oppression and brutality, and to assist our fellow human beings."

Yesterday, Harper spoke before a side panel focused on environmental issues at the United Nations. He told members of the panel that the global community needs to take a "flexible, balanced" approach to deal with global warming.

He said Canada wants to balance environmental protection with economic growth. He reiterated that position in a question and answer session after today's speech.

"If you go for hard caps as the only kinds of target (to limit global emissions), by definition the only countries that will sign on are countries that have no population growth and fairly limited economic growth. That's what happened with Kyoto."

Targets should apply to a range of economic realities, Harper said.

However, critics contend that Canada has joined an "anti-Kyoto" group opposed to mandatory greenhouse emissions cuts. Canada will officially join the Asia Pacific Partnership at the group's next meeting in New Delhi on October 15.