A U.S. law that would require all Canadians to show a passport before they can enter the country will cause severe economic damage and divide cross-border communities, Canadian top municipal leaders warn.

The Federation of Canadian Municipalities, which includes representatives of the country's largest communities, passed a resolution on Saturday asking the United States to delay the legislation until cheaper identification documents can be approved.

The law is scheduled to take effect at the end of 2006 for air and sea travellers. Land crossings, including at the U.S.-Canada border, will require a passport by the end of 2007, though the U.S. Senate recently asked for a 17-month delay.

"It will strangle the economy of this country," Toronto Coun. Howard Moscoe said in a news release announcing the resolution, which was made as Federation of Canadian Municipalities met in Montreal on the weekend.

The law, passed in the wake of the Sept. 11, 2001, attacks on the United States, would require a passport, electronic card or some other new mix of documentation for everyone crossing the border, including Americans returning home as well as Canadians heading south.

Currently, Canadians and Americans are able to cross the border with little more identification than a driver's licence or a birth certificate, though a passport has sometimes made it simpler to satisfy border officers.

Americans over age 16 must pay $97 US for a passport. The price is only slightly cheaper in Canada.

The federation's resolution calls for the deadline to be extended until alternative secure, inexpensive documents are available.

It also calls for an exemption for children to accommodate families and sports teams crossing the border.

Moscoe said because of the fees, an American family of four may decide to travel to Europe for a vacation instead of coming to Canada.

Vancouver mayor worried about Olympics

Vancouver Mayor Sam Sullivan expressed concern about how the new rules will affect the Olympic Games, scheduled for his city in 2010.

"Three months ago in Torino, I invited the world to come to Vancouver in 2010," Sullivan said.

"We're going to be representing Canada to the world, and it's very possible that this new regulation will make it much more difficult for these Games ... to be a success."

"If we permit this initiative to drive a wedge between our two countries, we will have given terrorists a victory."