The Conservative Party is nearly double the size previously claimed, as the first official figures published in five years show that membership is now at 124,000.

Brandon Lewis, the Conservative Party Chairman, said that the party membership had grown by 6,000 since Mrs May’s breakthrough Brexit deal in December, which paved the way for a two year transition period and talks on a future trade agreement.

The party is now only marginally smaller than the 130,000 registered during David Cameron’s premiership, with Mr Lewis indicating that he expected the figure to rise further in the coming months.

Speaking at the Conservative Spring Forum in London, Mr Lewis said that the party was also able to draw on the 350,000 part-time supporters who are part of Conservative clubs, many of whom “go out on weekends to make our case on the doorstep”.

The figures fly in the face of recent estimates put forward in a number of academic studies, with some experts claiming last year that the party membership had dipped below 70,000.