The Canadian government signaled on Thursday it was ready to crack down on Internet pharmacies that send cheap medicine to the United States, often without Canadian doctors having seen the patients.

The practice, which figured prominently in the U.S. presidential election campaign, had been seen as a way for American citizens and governments to save money. But it caused concern that it might lead to drug shortages in Canada.

“This is a struggle to make sure that drugs for all Canadians remain safe and adequate in terms of supply, and for all Canadians there’s a pricing regime that’s affordable,” Canadian Health Minister Ujjal Dosanjh told reporters.

He said options included making it illegal for Canadian doctors to countersign prescriptions from other countries or allowing doctors to write prescriptions only for Canadian residents or visitors to the country.

Another option would create a list of drugs that cannot be exported, if shortages or potential shortages develop.

The federal government had long allowed the Internet pharmacies to stay in business, particularly in light of the thousands of jobs they have created in the Prairie province of Manitoba. But Dosanjh said he was ready now to start moving.

“These are unethical, unprofessional transactions at their inception, and no state can turn a blind eye to it,” he said.

Drugs are cheaper in Canada than in the United States because of government price controls.

But pharmaceutical companies have warned that they would not supply hugely increased volumes of drugs to Canada if it became apparent that these were simply being shipped back to the States at cut rates.

Dosanjh noted that President Bush had expressed concern about the possible bulk reimportation of drugs into the United States.

“I am particularly concerned with respect to the feasibility of our pricing regime, and I want to make sure that that pricing regime remains in place at all costs because that means we are saving hundreds of millions of dollars,” the minister said.