Mexico and Canada are the United States’ top two trading partners, accounting for nearly 30% of trade volumes.

The 25% proposal marked an escalation from his campaign claims, as the ex-president previously proposed raising tariffs by 10%, or by 60% on goods imported from China—which is up from approximately 1% and 11% now, respectively, according to data from research firm Wolfe Research cited by the Wall Street Journal.

The move, announced on social media, threatens America’s largest trading partners over alleged failure to deal with illegal immigrants and drugs.