UKIP leader Gerard Batten has appointed former English Defence League leader Tommy Robinson as an adviser.
Mr Batten said he “looked forward to working with him” and that he would be advising him on subjects about which “he has great knowledge”.
The party said Mr Robinson, whose real name is Stephen Yaxley-Lennon, will advise on rape gangs and prison reform.
On Sunday, UKIP’s NEC deferred a decision on allowing members to vote on Mr Robinson joining the party.
The decision was postponed until after 29 March 2019 – the day the UK is due to leave the EU – with the NEC arguing the party should be focused on Brexit.
Currently, UKIP has a blanket ban on allowing former members of the British National Party and the EDL from joining the party – meaning the anti-Islam campaigner is barred.
Mr Batten added: “It is not necessary for him to be a party member in order to assist me in this role. I am looking forward to working with him”.
Last week, UKIP members of the Welsh Assembly said Mr Robinson should not be allowed to join.
In May, Mr Robinson, 35, was jailed for 13 months for contempt of court, which sparked a series of #freeTommy protests.
His conviction was later quashed over procedural concerns and the case has now been referred to the attorney general.