South Africa urged G20 countries to show global and cooperative leadership to tackle challenges including rising trade barriers, as the club's finance chiefs met on Thursday under the shadow of President Donald Trump's tariff threats.

"We are very unhappy, I am, with Russia," President Trump said while in a meeting with NATO Secretary General Mark Rutte.

Trump's tariffs could hit China, India and Brazil especially hard. All three countries are top buyers of Russian fossil fuels.

Alex Witt spoke with New York Times White House Correspondent Tyler Pager about what might be motivating President Trump to impose 30% tariffs on Mexico and the E.U. She also asked him about the President's upcoming announcement about Russia,

President Trump announced new tariffs against Mexico and the E.U. and also teased a big announcement involving Russia.

US President Donald Trump is threatening to impose a massive 500% tariff on countries that continue to buy Russian oil. What's this 500% tariff, you ask? Trump recently signaled he was backing a sanctions bill on Russia that would levy import taxes on countries doing business with Moscow,

President Donald Trump told reporters Tuesday that he plans to place tariffs of more than 10 percent on smaller countries, including nations in Africa and the Caribbean.