VICTORIA - A Vancouver businessman banned for life from entering the United States over his investments in American marijuana companies says he plans to seek a waiver that permits him to cross the border.

Canadian Sam Znaimer said he was recently denied entry at a Washington state border crossing by officials who said his investments in U.S. marijuana companies make him ineligible to enter the country.

"I spent four hours, four-and-a-half hours at the border station and at the end of that whole process I was told that I'd been permanently banned from entering the U.S.," he said in an interview.

Immigration lawyer Len Saunders said he's heard about a dozen similar cases recently where Canadians have been denied entry to the United States because of their connections to the marijuana industry.

"I'm getting panicked phone calls from Canadian companies who are concerned about their staff being denied entry and liability issues, or about themselves because they are senior executives," said Saunders, a Canadian whose law practice is based at Blaine, Wash.

Saunders said he tells Canadians working with American marijuana companies not to cross the border.

"You might as well be doing business with Pablo Escobar, selling cocaine in the U.S.," he said, adding marijuana is still a so-called schedule 1 substance in the U.S., defined by having no medical use and a high potential for abuse.

Znaimer said he's been investing in numerous business ventures for more than 30 years, including marijuana companies. He said he has participated in public panel discussions about marijuana and has been interviewed in the media.

"I'm purely an investor," said Znaimer.

The U.S. Customs and Border Protection office did not comment specifically on Znaimer's case, but said in a statement that medical and recreational marijuana may be legal in some U.S. states, but it remains illegal under U.S. federal law.

The statement said working in the marijuana industry, either in the U.S. or Canada, can still affect a person's admissibility to the country.

"Determinations about admissibility are made on a case-by-case basis by a (customs and border protection)officer based on the facts and circumstances known to the officer at the time," the statement said.

Znaimer said he was told he can't appeal the border decision, but has another option.

"I will apply for a waiver," he said. "I have no idea what my chances are of getting that. My lawyer is hopeful."

Saunders, who is Znaimer's lawyer, said the waiver process can take up to one year to complete and cost about US$600 in fees plus legal costs. He said the waivers are not permanent and people will likely have to reapply.

Saunders said he started seeing business people being barred from the U.S. in April.

"They said he was aiding and abetting the U.S. marijuana industry because of his investments," he said.

Znaimer said Canadians with any ties to the marijuana business in the U.S. should be wary about crossing the border.

"One distinction being made is that so far Homeland Security only seems to be interested in Canadians with some involvement in cannabis in the U.S.," said Znaimer.

Jordan Sinclair, a spokesman for Canopy Growth, the world's largest medical marijuana company, said facing a border ban is concerning, but it hasn't been an issue with anyone at the Smiths Falls, Ont., company.

"We've never had any challenges at the border," he said. "When I'm asked at the border what I do for a living, I tell them I work for a cannabis company, a federally regulated one."

Canopy Growth became the first cannabis-producing company to be listed on the New York Stock Exchange last May.

Former B.C. health minister Terry Lake, who now works for a Quebec-based medical marijuana company, said it is worrisome crossing the border for Canadians involved in the legal marijuana industry.

"I'm hoping to run in the Las Vegas half marathon in November," he said. "I would like to be able to cross the border without worry."