President Trump is being a royal pain to Prince Charles’ climate-change agenda.

Members of Trump’s inner circle have warned British officials that it would be counterproductive for Charles to “lecture” Trump on green issues during the president’s June visit to Britain, and that the president will “erupt” if pushed, the Sunday Times of London reported.

Trump has called climate change “a hoax.” Hours after he took office, references to the issue were removed from the White House website. By contrast, Charles has called climate change “the wolf at the door.”

A source close to Trump told the newspaper the president “won’t put up with being lectured by anyone.”