President Donald Trump dismissed Senate Minority Leader Chuck Schumer’s accusation that he was not serious about leveling a proposed tariff on Mexico.

“President Trump has a habit of talking tough and then retreating because his policies often can’t be implemented or don’t make sense … so I wouldn’t be surprised at all if President Trump doesn’t follow through on these tariffs, either,” Chuck Schumer said on the Senate Floor on Tuesday.

“Can you imagine Cryin’ Chuck Schumer saying out loud, for all to hear, that I am bluffing with respect to putting Tariffs on Mexico. What a Creep,” Trump wrote on Twitter.

Trump commented on Schumer’s criticism as the president’s trip to the United Kingdom continued.

The president defended his proposed tariffs on Mexico in response to the country’s failure to stop Central American migrants from traveling north to the U.S. border.

Schumer, he said, was only being partisan.

“He would rather have our Country fail with drugs & Immigration than give Republicans a win,” he said. “But he gave Mexico bad advice, no bluff!”