Published: 13:42, 30 April 2013 |
Updated: 16:14, 01 May 2013
Martyn Heale is the party's candidate in Ramsgate and was an active member of the National Front more than three decades ago.
UKIP rules bar anyone who has been a member of a far right organisation from being an election candidate, but party chiefs say that Mr Heale's membership of the National Front was considered historic.
He was also a member of the Conservative party in Ramsgate for 15 years, during which time he stood in various local council elections.
Mr Heale said in a statement he regretted joining the National Front.
"I have said on many occasions that I regret that youthful, and as it turned out, unwise decision to join.
"I categorically state that my NF membership was a bad decision and one that I sincerely regret."
He added that he denounced racism in any form and had not hidden his membership of NF from UKIP when he applied to join in 2003.
A spokesman for UKIP said Mr Heale had been a party member for several years before the ban was brought in.
"He joined the party long before the rule came in and it would be contrary to natural justice to backdate it and apply it to him."
Voters go to the polls on Thursday for what is expected to be the most keenly contested county council election for years.
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