Brexit campaigner Boris Johnson says PM May's party lost confidence; calls Conservatives to champion free market

Boris Johnson, Prime Minister Theresa May's former foreign secretary, said her Brexit plans were a constitutional outrage that would humiliate the United Kingdom by leaving it under the European Union's sway for generations to come.

"It would mean that UK business and industry, our entire economy, would be exposed perpetually to regulations that might have been expressly designed at the behest of foreign competitors to do them down," Johnson told the Conservative Party conference in the English city of Birmingham.

"It would mean that whatever the EU came up with in future ... all this nonsense we would have to implement with no ability to change or resist," he said. "That is not pragmatic, that is not a compromise - it is dangerous and unstable, politically and economically.

"My fellow Conservatives, this is not a democracy. That is not what we voted for," he said.