Commuters face delayed or cancelled trains at multiple stations this morning due to a signalling issue.

Trains between Shepherd's Bush / London Euston and Watford Junction may be delayed, revised or cancelled as a result of a fault with the signalling system. 

The incident was first reported by National Rail at 6.58am  and is expected to continue until at least 9.30am.

The fault is blocking the route used by Southern services between Shepherds Bush and Wembley Central, according to National Rail, meaning some services to Watford Junction will terminate early at Shepherds Bush.

Some trains from Watford Junction will instead start from Shepherds Bush.

National Rail has warned Southern is unable to go via Wembley Central, Harrow and Wealdstone or Watford Junction at present, meaning commuters will need to use an alternative route for these stations and leave at least 30 minutes of extra time to do this.

Southern train tickets are being accepting on London Underground, bus services, London Overground, and London Northwestern Railway services between London Euston, Harrow & Wealdstone and Watford Junction.