President-elect Donald Trump’s promise to launch a mass deportation of millions of undocumented people is a top focus for Canada, its deputy prime minister said Friday, as the country plans to deal with a possible influx north.

California immigrant advocates and state officials are bracing for what they describe as the likely massive impact of a second Trump presidency on border policies — vowing to fight his plans in court even as they remain uncertain which will make it from the campaign trail to reality.