Cllr Aaron Callan will remain a member of the party.
A County Derry-based councillor has resigned as group leader of his party's council delegation.
Cllr Aaron Callan, from Limavady, confirmed to Derry Now that he had stepped down from the position, but still remained a member of the DUP.
Cllr Callan was first elected to Causeway Coast and Glens Borough Council in 2014, while still a member of the Ulster Unionist Party (UUP).
He joined the DUP in 2016, telling Derry Now in an interview earlier this year that his decision was taken because the UUP was 'no longer favourable for unionism'.
In more recent times, Cllr Callan has been a leading voice in plans for the Causeway International Air Show, set to take place in 2022.
Aside from confirming his resignation and party membership, Cllr Callan said he could not comment further on internal party business.
Alderman John Finlay will temporarily assume leadership of the council's DUP grouping, acting as nominating officer.
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