U.S. president Richard Nixon (right) talks to Canadian Prime Minister Pierre Trudeau while they sit in armchairs at the White House in Washington, D.C., in December 1971. (Hulton Archive/Getty Images)

A taped conversation that led former U.S. president Richard Nixon to call then prime minister Pierre Trudeau a "pompous egghead" has been released publicly.

The two-hour discussion that took place on Dec. 6, 1971, in the Oval Office is believed to be the only exchange between the two leaders captured on the infamous Nixon recording system.

The recording, parts of which are scratchy and inaudible, was found among 200 hours of tapes and 90,000 pages of documents recently released by the Nixon Library.

In the recording, Nixon is heard asking his aides for guidance on how to "lead" that "son-of-a-bitch" Trudeau before the meeting begins.

At times during the conversation, Nixon seems to grapple to articulate his administration's intentions when it comes to trade relations with Canada and then security adviser Henry Kissinger occasionally weighs in to provide the Canadian prime minister with more details.

Nixon also demonstrates some paranoia, telling Trudeau that other countries are "ganging up" on the United States on trade issues.

Trudeau then lectures Nixon on economics related to the Americans' controversial shift toward more protectionist practices against its trading partners, including Canada.

"If you're going to be protectionist, let's be in it together," Trudeau tells Nixon. "I am not a nationalist. I am not a protectionist ... If you were going to take a very protectionist trend, our whole economy is so importantly tied to yours, we'd have to make some very fundamental decisions."

Trudeau says the U.S. could easily build up a trade surplus with Canada in an attempt to essentially colonize the country.

"If we're always in debt towards you, the only way in which we can pay our debts is by selling you parts of our country. This is a question, Mr. President, that is causing concern in Canada," Trudeau says.

Trudeau goes on to hint that Canada may be forced to enter into trade agreements with other countries in response to U.S. protectionism.

Canada 'terribly important' to U.S.

Nixon tells Trudeau that Canada is a close friend and "terribly important" to the United States but doesn't make any commitments on the trade issues being discussed.

"Both the U.S. and Canada are inevitably going to pursue their own interests ... They have to do that," says Nixon.

It is Kissinger who eventually intervenes to tell Trudeau that Canada will soon get a fairer shake while Nixon is heard making noises in the background.

"That is extremely helpful," Trudeau tells Kissinger. "I think we're reassured by everything you've said, that this is temporary, [that] this is not a philosophical approach that we want to keep you in a state of domination just because we want to protect our society now, and we'll go back to being more or less free traders ... This is the most important reassurance I can take home."

It is only then that Nixon admits that the long-term goal is to move toward freer trade, not more protection.

As the tape continues to run, Nixon is heard cursing Trudeau and calling him a "pompous egghead" after the meeting ended. He then asks Kissinger what Trudeau was talking about.

To his chief of staff, H.R. Haldeman, Nixon fumes, "That Trudeau, he's a clever son of a bitch" and orders him to plant a negative story about the prime minister with a syndicated columnist.

Trudeau later learned of Nixon's comments, which have been previously released, and quipped that he'd "been called worse things by better people."

Despite the contents of the tapes, Timothy Porteous, Trudeau's executive assistant from 1968 to 1973, insists the two leaders had an amiable relationship.

"On a personal level, believe it or not, it was very friendly," Porteous said in a recent interview.

"Nixon was an ingratiator, and he was always trying to get the approval of whoever he was speaking to," Porteous said. "If he thought it would win him approval to call Pierre Trudeau names, then he'd call Trudeau names."

With files from the Canadian Press