Passengers on the Eurotunnel are this evening experiencing long delays after power supply problems in the Channel Tunnel.

It has been causing a severe backlog of traffic at the Folkestone terminal while technicians clear the fault.

Services were being delayed by at least an hour and a half and Eurostar services via Ashford International to London St Pancras were also affected.

A Eurotunnel spokesman confirmed an incident earlier this afternoon meant engineers had to carry out essential maintenance work in the tunnel.

They said it had reduced operations to a single line, causing a backlog.

It was hoped services would be running normally again by 6pm.

Traffic on the nearby M20 motorway has so far not been affected.