Former prime minister Stephen Harper visited the west wing of the White House on Monday, at a time of heightened tension between the Canadian and U.S. governments.

U.S. media report that Harper met White House economic adviser Larry Kudlow. Harper did not publicly confirm that meeting, but he did share a photo of his meeting with Republican Party co-chair  Bob Paduchik.

Harper also tweeted that he met with International Republican Institute President Daniel Twining “to discuss building democracy around the world.”

CTV News learned last week that Harper was expected to meet Kudlow, as well as American National Security Adviser John Bolton, during his trip to Washington, D.C.

The trip came as a surprise to Prime Minister Justin Trudeau’s government, which has recently been the target of criticism by U.S. President Donald Trump’s administration over trade.

Canada imposed tariffs on steel, aluminum and more than 70 other U.S. goods on Sunday, in a dollar-for-dollar response to U.S. tariffs on Canadian-made steel and aluminum that began on June 1.

At a briefing on Monday, White House Press Secretary Sarah Sanders did not answer a reporter who asked why Harper was at the White House.

However, she did address a question about Canada’s tariffs.

“We’ve been very nice to Canada for many years and they’ve taken advantage of that, particularly advantage of our farmers,” Sanders said.

“At the G7, the president actually proposed that they get rid of all tariffs and drop all barriers and have really great trade and they refused that,” Sanders added.

Since resigning as leader of the Conservative Party after his 2015 electoral defeat, Harper has written a book, started a consultancy firm and is serving as Chair of the International Democrat Union (ID), an alliance of centre-right political parties.

Lori Williams, a professor of political science at Mount Royal University, said that meeting Bolton and Kudlow during the trade dispute could be “very significant” considering that Trump’s tariffs were created on national security grounds.

Although many have expressed concern that Harper could undermine the efforts of the Trudeau government, Williams tells CTV News Channel that Harper appeared careful not to do so in a recent interview on Fox News.

“On Fox, he emphasized the mutual benefits of economic trade between Canada and the United States and focused on the fact that we’re national security allies and not adversaries, distinguishing us from China and focusing on our shared interests,” Williams said.

“He’s part of an international community still that’s centre-right, provides advice and policy recommendations and so forth, and from that position may be able to appeal to conservative advisers perhaps in way that Prime Minister Trudeau cannot,” she added.