On a Sunday caucus call just one day after Prime Minister Mark Carney told Canadians the White House’s latest tariffs amounted to a “new attack on Canada,” Canada-U.S. Trade Minister Dominic LeBlanc asked MPs to be careful with what they say on social media and to decline requests to talk trade on American networks.

Prime Minister Carney emphasized that advice when he joined the call, according to one of the sources. Part of the government’s thinking is that MPs should be cautious with media because they are not fully aware of every single detail in the trade negotiations.

“We’ve decided as a federal government months ago not to respond to sort of the daily social media posts of either the president or his cabinet secretaries and so on,” LeBlanc said during an interview Tuesday, after he was asked about a series of social media attacks from U.S. President Trump.

Speaking on CBC, former cabinet minister Lisa Raitt, a member of the federal Canada-U.S. trade advisory council, said: “the United States is watching very carefully the commentary in the media being made by Canadians.”

“Any word that’s been uttered in the last 24 to 48 hours is going to be pored over and scrutinized by the U.S., by the trade teams who are negotiating,” Raitt said. “Anything that we say here that could harm negotiations, I think is not necessarily a good thing, quite frankly.”