WASHINGTON - Seven Canadian premiers met with a pair of key White House power brokers Friday in advance of their attendance at an influential conference of American governors.

The leaders of Quebec, Ontario, Manitoba, Saskatchewan, New Brunswick, Nova Scotia and Prince Edward Island discussed the economy and efforts to reduce greenhouse gas emissions with President Barack Obama's economic czar, Larry Summers, and Lisa Jackson, head of the Environmental Protection Agency.

Saskatchewan Premier Brad Wall said he and his counterparts raised concerns that Canadian manufacturers might be subject to punitive measures from the U.S. now that the EPA has warned it will start regulating carbon emissions, a simmering hotspot in Canada-U.S. relations.

"There's an awareness of that concern and I think a general acknowledgment that this is an issue that's going to have to be resolved by way of international agreement as opposed to unilateral action," Wall said after the meeting with Jackson.

Quebec Premier Jean Charest urged Jackson to consider hydroelectric power as a renewable resource, said his New Brunswick colleague, Shawn Graham.

"She had her full team there," Graham said. "We had a good opportunity to talk about our efforts to reduce greenhouse gas emissions."

Economic recovery and trade issues, he said, were top items of discussion with Summers.

"It was insightful to hear how the U.S. economy was recovering," he said.

"We did talk about the importance of trade between our two countries, and there was a small discussion about past trade irritants, including softwood lumber. The premiers stressed the importance of open trade between our two countries -- it was a respectful dialogue."

Ontario Premier Dalton McGuinty agreed.

"I like to think that under this Administration there's a greater level of receptivity to Canadian concerns," he said.

The meeting with Jackson came in the midst of tough talk by the EPA that it will begin to crack down on carbon emissions in the absence of greenhouse gas legislation from Congress. That legislation is stalled after the Democrats recently lost their filibuster-proof majority in the Senate with the election of a Republican to the late Ted Kennedy's Massachusetts seat.

Canadian manufacturers could suffer due to the EPA's involvement if Washington opts to impose protectionist barriers on oil and other goods made from carbon-intensive industries north of the border.

Charest, for his part, said he planned to push Jackson to allow hydroelectric projects to become eligible for green energy subsidies in the United States. Quebec has several such projects, and a number of U.S. states are onside with Charest on that request.

"We would like recognition in American legislation of large-scale hydro," he said earlier Friday, adding such recognition "would create an incentive to sell more energy and more renewable energy to the United States."

He added that Canada has a safe and abundant supply of energy to sell to the United States.

"For Americans here -- we saw it during the last election campaign -- energy is a security issue. Well, we happen to be a very reliable neighbour and partner in the area of energy."

Wall is leading the delegation of premiers as chairman of Canada's Council of the Federation. On Saturday, the premiers will be at two roundtables on energy and the environment at the National Governors Association meeting.

The premiers aren't exactly on the same page on environmental issues. Charest has criticized Ottawa for its insistence that Canadian greenhouse gas policy must be in lockstep with the Americans, while Wall and other oil-producing provinces are in agreement with the feds that the U.S. and Canada must be in synch.

Trade issues will again dominate a Sunday meeting with U.S. Agriculture Secretary Tom Vilsack. The premiers are expected to raise concerns about the U.S. country-of-origin labelling rules on Canadian meat and other food products.

Canada and Mexico have complained to the World Trade Organization about the practice, saying it violates NAFTA.