Eurosceptic businessman Arron Banks has announced that he will not contest the Clacton constituency at the general election, as he had previously said he would.

The millionaire former Ukip donor had previously announced that he would fight the the Essex seat in order to undermine Douglas Carswell, who defected from Ukip to become an independent earlier this year.

However Mr Carswell last week said he would be standing down as an MP at the June 8 general election and thrown his support behind Theresa May, describing her as a real “revolutionary”.

Mr Banks, a close ally of Nigel Farage, is now backing his local Ukip candidate, who he described as a “very hard working decent bloke”. He added that he did not want to “leap over” his Ukip colleague.

The former Ukip donor, who co-founded the Leave.EU campaign for last year’s EU referendum, described Mr Carswell as a “hugely divisive figure and let a lot of people down in Clacton”.

He said: “Douglas Carswell is the epitome of a nasty little career politician who didn't give two hoots for the area.

“He stood originally for Ukip because he knew they would win the seat in a general election. He used Ukip and did nothing for Clacton.”

The rise and rise of Ukip – the new party of the protest voter Show all 3 1 /3 The rise and rise of Ukip – the new party of the protest voter The rise and rise of Ukip – the new party of the protest voter 30-ukipprotest-gt.jpg Onwards: UKIP are hoping to take off Getty Images The rise and rise of Ukip – the new party of the protest voter 30-ukipprotest2-gt.jpg UKIP's Rotherham candidate Jane Collins Getty Images The rise and rise of Ukip – the new party of the protest voter 30-ukipprotest3-gt.jpg In 2010, leader Nigel Farage was injured when the light aircraft he was travelling in crashed Getty Images

After the news of Mr Bank’s standing down broke, Mr Carswell tweeted, apparently referring to the Leave.EU campaign: “Can you imagine what the EU referendum result might have been if Vote Leave had lost the designation battle to the other lot?”