Ukip Welsh assembly member and former MP Mark Reckless is rumoured to be considering defecting back to the Conservative Party, but is likely to be blocked from doing so.

Mr Reckless defected to Ukip in 2014 and defended his seat in a by-election but lost it again at the general election, and has been a member of the Welsh Assembly since last year. He is alleged to have applied to re-join the Conservatives and sit alongside them in the Assembly, but sources suggest he will be formally prevented from doing so.

Mr Reckless and Douglas Carswell both caused problems for the Conservatives when they defected and won by-elections prior to the 2015 general election. Mr Carswell has recently quit the party.

Nigel Farage, the former Ukip leader told The Telegraph: "I will be very sad to see the back of him. Unlike Mr Carswell I have always thought him an honourable person. I'm sure the pressure on him has been enormous over the last week."

The Welsh assembly is elected on a list system in which people vote directly for parties, not for people. It means Assembly Members cannot claim to have any real personal mandate, making defecting even more difficult politically.

In 2014, David Cameron, the former Prime Minster, told several audiences at that year's party conference, that he would proudly lead the campaign against Mr Reckless in the Rochester by-election, and accused him of disloyalty to the party organisers and activists who had worked hard to get his "fat arse" in to the Commons.

Mr Reckless defeated the Conservative candidate Kelly Tolhurst in the November 2014 by-election, bu Ms Tolhurst defeated him seven months later, by 7,000 votes.