Independent councillor s Reform UK
BBCAn Independent councillor has ed Reform UK, saying change was "much-needed".
Chester-le-Street South councillor Paul Sexton's ing the party means it has pushed its overall majority back up to 65 councillors, following Andrew Kilburn's resignation on Monday.
Sexton, who has been an Independent with Durham County Council since 2017, was re-elected alongside fellow Independent councillor Bill Moist on 2 May.
Speaking about the switch in allegiance, he said Chester-le-Street "needed a voice on the inside".
Instead of sitting in opposition, he will work alongside the party's 64 other in overall control of the authority.
Sexton previously held the role of cabinet member for adults and health services but resigned in protest at the management of the council by the former t istration, made up of Liberal Democrats, Conservatives and Independents.
Andrew Husband, also of Reform UK, was elected to the neighbouring Chester-le-Street North ward.
Sexton said: "Reform has a huge mandate to effect the much-needed change in County Hall and I have the experience to this initiative.
"Chester-le-Street needs a voice on the inside if we're to achieve the much-needed investment that our fabulous town deserves."
Local Reform officials said they expected more county councillors to the party, the Local Democracy Reporting Service said.
A Reform spokesman said: "We're delighted Paul Sexton has ed us.
"We welcome anyone who shares our vision for integrity, ability, and meaningful change to us."