Entrepreneur John Mills quits Vote Leave for Labour Brexit group
Labour donor John Mills has quit the cross-party Vote Leave campaign saying he wanted to concentrate on making his party's case for Brexit.
Mr Mills had been deputy chairman of the group designated the lead "out" campaign by the Electoral Commission.
He has previously claimed the campaign was torn by internal feuding.
He was reported to have been on the verge of quitting in February when Labour MP Kate Hoey joined a rival out campaign.
In his resignation letter, the home shopping magnate said he had "come to believe that it would be useful and more effective for the Leave campaign if there was a strong and independent Labour voice for the arguments to leave the EU".
"I can now focus fully on my role as ... director of Labour Leave, and create that distinctive voice," he said.
"In the run up to the vote on 23 June, Labour Leave will provide a compelling and robust left-of-centre case for leaving the EU."
The vast majority of Labour MPs are in favour of Britain remaining in the EU - with about a dozen campaigning for an exit.
Labour former minister Frank Field has warned the party it risks losing "a swathe" of voters to UKIP by campaigning to remain in the EU.
Mr Mills, who played a leading role in the 1975 referendum campaign against EU membership, has also been critical of Jeremy Corbyn's decision to back staying in.
He said: "I hope this decision will be a transformative first step to motivating Labour people who are still unsure how they will vote, to vote Leave in June to secure a better, fairer future for this country.
"Labour Leave will continue to work with Vote Leave, as well as other Leave campaigns across the piece, to secure a stronger future for the UK outside the EU."
Vote Leave was the organisation chosen by the Electoral Commission to take the lead in making the case for Britain to leave the European Union. It is headed by big Conservative names Boris Johnson and Michael Gove and Labour MP Gisela Stuart with support from Lib Dem and UKIP figures, as well as business people.
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