U.S. President Donald Trump promised a big trade deal for post-Brexit Britain to Boris Johnson on Sunday and praised the new prime minister as the right man to take Britain out of the European Union.

Johnson, who faces a delicate task of assuaging European allies while not angering Trump at a Group of Seven summit in France, said trade talks with the United States would be tough but there were huge opportunities for British businesses in the U.S. market.

Speaking to reporters with Johnson ahead of a trade-focused bilateral meeting, Trump said Britain's membership of the EU had been a drag on efforts to forge closer trade ties.