WORCESTER, Mass. – U.S. Ambassador to Canada Paul Cellucci says he has told Canadian leaders that their proposal to decriminalize marijuana for personal use would result in much-tighter security along its 5,500-mile border with the United States. Maine has 611 miles of that border, with Canada’s Quebec and New Brunswick provinces.

More vehicles would be stopped and searched at crossing checkpoints that already have high security since Sept. 11, 2001, the former Massachusetts governor told The Telegram and Gazette of Worcester.

“If the perception is that it’s easier to get marijuana in, then some border officials’ antennas will be up,” Cellucci said. “We don’t think it’s a good thing, and there will probably be more inspections.”

Caches of Canadian-grown marijuana have been increasingly found in recent drug busts in Massachusetts and other states, which worries him, Cellucci said.

Canadian lawmakers last week proposed a new marijuana law that would eliminate a criminal record for possession of marijuana in small amounts while spending millions to spread an anti-pot message.

Under the measure introduced in Parliament, getting caught with 15 grams – about half an ounce – or less of marijuana would bring a citation akin to a traffic ticket, not a criminal record. Possession of marijuana would remain illegal and the maximum sentence for illegal growers would be increased by double to 14 years in prison.

Cellucci’s expression of U.S. positions toward its largest trading partner have been more vocal than many predecessors, including the time he publicly accused Prime Minister Jean Chretien’s government of deserting the United States by not supporting the then-impending war on Iraq.

Traditionally, many ambassadors to Canada have seen their roles as largely ceremonial.

“He is markedly different. His predecessors have really been a shadow of American foreign policy, whereas Mr. Cellucci has really been an evangelist of sorts, and much stronger,” said Rob M. McGowan, editor of Politics Canada, the country’s biggest independent political Web site.

“He’s really been very, very vocal. He doesn’t whisper things in perfumed diplomatic corridors,” McGowan said. “It’s done before large groups. It’s definitely tempered by diplomacy. You might not agree with what he says, but at least he says it directly.”