UPDATE: 11.20am
There's congestion up to the A4137 junction.
UPDATE: 8.38am
A South Wales Fire and Rescue Service spokeswoman has said that the fire has been put out.
She said that crews from Monmouth attended to the fire.
UPDATE: 8.30am
The car on fire has also been involved in a crash.
8.20am
A car fire is blocking the A40 between the Gibraltar Tunnels and Raglan.
Traffic is blocked and stationary westbound between the tunnels at Mitchel Troy and Raglan.
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