Traffic is mounting on several major roads after an M25 crash this morning (January 16).

Two lanes were closed between junction 19 near Watford and 18 for Chorleywood after a collision on the anticlockwise carriageway caused hour-long delays.

The stretch has been reopened but rush-hour congestion is persisting at several points back to junction 22 for St Albans.

There are also knock-on delays affecting the A1, A414, A41, and M1 southbound near Watford.

The worst of the M25 congestion is by junction 21a for the M1, and junction 20 for the A41 near Kings Langley, according to Google Maps.

The A41 by The Grove hotel and The Dome roundabout in North Watford also has heavy traffic.