A van burst into flames on the M25 on Wednesday morning, bringing the busy motorway to a standstill.
There were 45 minute delays on the ring road in Surrey between Redhill and Godstone as firefighters tackled the incident, National Highways said.
The fire shut all lanes on the M25 at around 8.25am on Wednesday with traffic building since.
The road has since reopened.
Railway lines shut by a trackside fire in Brockley also reopened on Wednesday morning.
The blaze brought trains to a standstill between Sydenham and New Cross Gate on Tuesday.
Network Rail warned the fire damaged cables that supply electricity to the railway, causing heavy disruption to trains between London Bridge and Crystal Palace.
London Overground services were also partially suspended.
In an update around 5.45am on Wednesday morning, National Rail said the lines had reopened and services were no longer disrupted.
