Vicente Fox, the former president of Mexico who served from 2000 to 2006, brought his Twitter beef with the current U.S. president to Comedy Central’s The Opposition. Midway through Jordan Klepper’s segment on Trump’s southern border wall, Fox made a surprise entrance, and he didn’t hold back. Mexico will “never pay for that fucking wall,” Fox told the host. During the interview, Fox defended the Mexican immigrants living in the United States, and spoke of America’s greatness in non-Trump terms. He also got in some pretty solid barbs about Trump’s “mediocre” business record and what it means to be presidential.