An American legislator called Canada "parasitic" on Wednesday for siphoning U.S. dollars to Canada with low prescription drug prices while his country does "all the innovation."

Canada benefits financially from America's role as a world leader in medical advances, Republican Senator Bob Corker charged in an exchange with a Liberal MP as she testified before a U.S. Senate committee.

"One of the things that has troubled me greatly about our system is the fact that we pay more for pharmaceuticals and devices than other countries, and yet it's not really our country so much that's the problem, it's the parasitic relationship that Canada and France and other countries have towards us," the Tennessee lawmaker told Carolyn Bennett.

"Meaning that you set prices and unfortunately all the innovation, all the technological breakthroughs, just about, take place in our country .… You benefit from us, and we pay for that, and I resent that."

Bennett, a family doctor and one-time minister of state for public health, was one of five people testifying before the Senate special committee on aging. The panel, chaired by Democratic Sen. Herb Kohl and including newly minted Sen. Al Franken, was examining how successful health-care systems keep their costs low while maintaining quality care.

She seemed puzzled by Corker's remarks, reminding him that drug pricing was a global concern, not part of a plot by Canada.

"It's the drug companies, sir, and they're multinational — it's nothing about the United States of America," she told him.

Their debate comes as U.S. Democratic senator Byron Dorgan from North Dakota is preparing to make a legislative push in the days to come that would legally allow Americans to buy cheaper Canadian drugs.

Dorgan will introduce an amendment to the health-care reform legislation currently before the Senate finance committee that would legalize so-called re-importation. Under current U.S. law, only pharmaceutical companies are allowed to import prescription drugs approved by the Food and Drug Administration into the United States.

Drug companies import more than US $40 billion in drugs into the United States, while drug wholesalers and consumers are shut out of the global marketplace. Consequently, Dorgan has long maintained, Americans pay higher prices for prescription drugs than anywhere else in the world.

News of the pending amendment, to be introduced when the health-care reform bill makes it to the Senate floor, has alarmed some Canadian observers who fear re-importation could lead to shortage of drugs in Canada.

Bennett herself raised that concern in her testimony on Wednesday.

"Please don't think that you can import cheap drugs from Canada … it will last us about 36 days," she told Corker.

He replied: "That's a silly way of dealing with it."

"My goal over time is for us not to pay more than you, because you set prices and cause us to pay more when we're doing all the innovation," Corker added.

"In essence, the Canadian government and its citizens are taking advantage of our citizens by virtue of setting prices that are lower than competitive prices."