Boris Johnson is preparing to impose full customs and border checks on all European goods entering the UK after Brexit, in a ramping up of pressure on the coming EU-UK trade talks, the Telegraph has learned.

In a radical departure from pre-election ‘no deal’ planning that prioritised the smooth flow of goods into the UK from Europe, Whitehall departments have been told to prepare for imposing the full panoply of checks on EU imports to the UK.

The toughened approach, which is designed to give UK negotiators greater leverage against Brussels, came as Mr Johnson promised that Brexit would open an exciting new chapter “in our great national drama”.

“I know that we can turn this opportunity into a stunning success and whatever the bumps in the road ahead, I know that we will succeed,” he said. “Now is the time to use those tools to unleash the full potential of this brilliant country and to make better the lives of everyone in every corner of our United Kingdom.”

His address to the nation came as revellers gathered across the country to celebrate ‘Brexit hour’, at 11pm, with the Brexit Party leader Nigel Farage hosting an event in Parliament Square which was festooned with Union flags for the occasion.