OAKVILLE, Ont. — Prime Minister Justin Trudeau is refusing to comment on the future of TikTok in the United States, at a time when his own party is leaning on the app and its influencers to deliver the Liberals’ political message to Canadians.

The U.S. Senate passed a bill Tuesday that would force TikTok’s parent company, Beijing-based ByteDance, to sell its share of the social-media app within a year or face a ban in the platform’s largest market.