Tom Mulcair says he has nothing to learn from Conservatives about how an official Opposition leader should comport himself when travelling outside Canada.

Indeed, the NDP leader says the Tories — who've been bashing him all week for allegedly "trash talking" Canada during a visit to Washington and New York — seem to have forgotten the way they behaved in Opposition.

'People can take that with a grain of salt'—NDP leader Tom Mulcair

"All of a sudden there's a rule that they've decided that you're not supposed to talk about the government (while abroad) now that they're the government but when they were the Opposition there was no problem talking about the government," Mulcair said in an interview at the conclusion of his trip.

"So people can take that with a grain of salt."

When Prime Minister Stephen Harper was in Mulcair's shoes, he didn't hesitate to denounce the Liberal governments of the day to American audiences.

He co-wrote a 2003 article in the Wall Street Journal bemoaning Chretien's "serious mistake" in refusing to join the U.S.-led war in Iraq.

"For the first time in history, the Canadian government has not stood beside its key British and American allies in their time of need," he wrote.

He made his own obligatory trip to Washington in 2005, where he stoked American fears that Canada was soft on terrorism. Among other things, he accused Liberals of consorting with ethnic groups that were linked to terrorist organizations.

Before becoming official Opposition leader, Harper gave a notorious speech — albeit in Montreal — to the U.S. Council for National Policy, in which he derided Canada as "a northern European welfare state in the worst sense of the term."

By that standard, Mulcair's criticisms of the Harper government's environmental record and his lack of enthusiasm for the Keystone XL pipeline were relatively tame.

But his musings were clearly unwelcome to the government, coming just as cabinet ministers and western premiers were on a charm offensive aimed at quelling Americans' anxiety about the environmental impact of the pipeline, which would carry Alberta oil sands crude to Gulf Coast refineries.

Environmental record

Foreign Affairs Minister John Baird clucked that Mulcair was "trash talking" Canada, undermining efforts to win approval for the pipeline. Saskatchewan Premier Brad Wall accused him of "betraying Canadian interests."

Nonsense, Mulcair said.

"These are important moments where you get to define who you are as the official Opposition and a government-in-waiting. So, of course, you're going to be saying what the differences are with the sitting government," he said.

"Nothing new about that and certainly nothing unusual about that. You know, it's a compulsory figure."

Moreover, Mulcair insisted he said nothing to his various American audiences that he hasn't been saying for months back home in Canada about the Tories' lamentable environmental record and the NDP's preference for sustainable development of natural resources, creating value-added refinery jobs in Canada and building a pipeline to carry western oil to the east coast.

"Surprising as it might sound to some of the Conservatives and those who work with them, Americans do know how to read," Mulcair said.