An articulated lorry containing meat went on fire at Carew roundabout shortly after 7.30 am on Saturday.
A tyre-blow out on the trailer of the Irish- registered vehicle - contained 30 tons of meat - led to the tyre catching fire.
The driver stopped the lorry and detached the cab from the trailer. The rest of the trailer's tyres were well alight on the arrival of the fire brigade.
Fire crews from Tenby and Pembroke Dock, wearing breathing apparatus sets, used a hose reel jet, a jet and a foam-making branch to tackle the blaze and cool the diesel tank. A water bowser was also in attendance.
Although the blaze was under control within half- an-hour, firefighters remained at the scene to cool down the vehicle's diesel tank and to supervise the removal of the meat from the trailer in case any 'hot spots' remained.
The A477 closed while firefighters tackled the blaze and when a crane was brought in to unload the trailer, which resulted in congestion and traffic jams for motorists.