Motorists are being warned of mounting congestion on the M25 near the M1 junction following a diesel spillage this morning (July 3).

https://twitter.com/HighwaysEAST/status/1014029653194018816

Two lanes have closed on the clockwise carriageway near Junction 21, and Highways England has said that delays are starting to build on the approach.

No-one is thought to have been seriously injured.

Updates to follow.