Chrystia Freeland, the former Canadian finance minister who helped bring Justin Trudeau’s political career to an end when she resigned in December, has joined the race to replace him as prime minister.

The source, who was not authorized to speak publicly about the announcement, also said Freeland’s first policy promise will be to impose dollar-for-dollar retaliatory tariffs on U.S. imports to match the tariffs U.S. president-elect Donald Trump has vowed to impose on Canada.

Former finance minister and deputy prime minister Chrystia Freeland is expected to announce a bid for the Liberal leadership within the week, sources have told Radio-Canada.