LONDON (AP) — A senior adviser to British Prime Minister Boris Johnson has dismissed concerns about tensions arising from Parliamentary debates over Brexit, telling supporters that it isn't surprising that people are upset about the country's failure to leave the European Union.

The prime minister has been accused of whipping up division with his charged language about Brexit opponents in the House of Commons this week.

But Dominic Cummings told backers at a book launch that the only way to calm tensions is for lawmakers to respect the results of the 2016 referendum.

He says the current chaos is "a walk in the park" compared with the 2016 referendum campaign in which the country narrowly voted to leave the EU. Three years later, Britain and its politicians remain bitterly divided over how, or whether, to leave the 28-nation bloc.