One lane has been reopened northbound on the A34 after an accident.
One lane remains closed on north and southbound.
The northbound carriageway was completely closed following an incident in which an HGV crossed through the central reservation, damaging the safety barrier and spilling diesel onto the carriageway.
The vehicle has now been recovered and Highways Agency contractors are currently in the process of repairing the safety barrier.
The carriageway is due to fully open in both directions once this work is complete.
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