WASHINGTON - NDP Leader Jack Layton says Canada and U.S. Democrats should work together to improve NAFTA's environmental and labour standards.

Layton, who was in Washington yesterday, says NAFTA shouldn't be the model for other trade pacts around the world because it benefits businesses much more than workers.

Both Hillary Clinton and Barack Obama have promised to reopen NAFTA as part of their pitch to working families as they campaign for the Democratic presidential nomination.

Layton complains Canadians are working five weeks more a year than they did nine years ago, but half of all families are making less money.

Meantime, he says, Canada's top chief executive officers make 218 times more than the average Canadian.

Layton made the comments at an event hosted by the Campaign for America's Future, which is focused on pushing a progressive agenda if a Democrat wins the White House this fall.