Commuters faced delays of up to 40 minutes on Wednesday morning after a large vehicle transporter caught fire on the M25.
Six fire engines and 30 firefighters attended the scene between junction 24 and 25 after the vehicle, carrying 10 cars, was engulfed in flames.
Traffic on the westbound side of the motorway was brought to a standstill by the blaze.
It is not yet known how the fire began.
Highways England said that ongoing clean-up and recovery operations meant that delays could continue and suggested that drivers consider alternative routes.