SURREY, B.C. - The nuclear crisis unfolding in Japan following last week's massive earthquake and tsunami poses no risk to Canada, says Prime Minister Stephen Harper.

Harper said officials at several federal agencies believe the radiation leaking from a damaged nuclear power plant in Japan won't put Canadians at risk here at home.

"I've been in very regular contact with various agencies in government responsible for monitoring this, and there is no evidence of a scenario that presents any risk to this country," Harper told reporters Tuesday following an unrelated announcement in Surrey, B.C.

"They do not see any scenario where this presents a risk to Canada. We just simply do not see that as being plausible."

Harper added the greater concern is ensuring Japan has everything it needs to deal with the disaster, and he said Ottawa has offered to help.

He predicted Japan will take up the offer.

"We've made it very clear to the Japanese government there's a range of various services or supplies that we could offer if so desired, and I gather there's a couple of things that they will call on us to assist with."

The earthquake and tsunami are believed to have killed more than 10,000 people. The twin disasters also severely damaged a nuclear plant on Japan's eastern coast.

Dangerous levels of radiation have started leaking at the facility, prompting officials to order nearly 150,000 people to stay indoors. About 70,000 more who live near the facility have already been ordered to leave.

That has prompted some Canadians to worry that harmful radiation could cross the Pacific and affect people living here.

Some pharmacies in British Columbia have reported customers asking for potassium iodide, which is thought to help protect the thyroid from radioactive iodine contamination.

British Columbia's health officer Dr. Perry Kendall is encouraging residents to resist the urge to stockpile potassium iodide because it's not necessary.

Kendall has said it would take five or six days for any radiation to cross the Pacific, and by that time it would have dispersed into the atmosphere.

The province's public safety minister has also attempted to reassure British Columbians that they're not at risk.