At the time, Russia said that any US attempt to compel countries to use the dollar would backfire.

The Brics grouping includes Brazil, Russia, India, China, and South Africa and a few other countries that joined in the past couple of years.

Trump posted his warning to the Brics as Canada and Mexico await for his decision to follow through on a pledge to impose 25% tariffs on the US' North American trading partner from Saturday.

Trump wants to use tariffs as a tool to get Mexico and Canada to help stem the flow of illegal drugs into the US, particularly the deadly opioid fentanyl, and also migrants crossing illegally into the US.