The Beddingham roundabout near Lewes on the A27 is blocked by an overturned lorry.
Emergency services were called at 6.50am this morning (Tuesday September 16) to an articulated lorry which had rolled over and was blocking the carriageway.
No other vehicles were involved and the driver suffered an injury to his arm.
The lorry was carrying compost and clearing it up is expected to last most of the day.
Traffic is being directed around the lorry in a contraflow and motorists are being asked to avoid the area if possible.
Congestion is being reported on the A27 Lewes Road to the A2270 Polegate by-pass.
Westbound queues are reported as being more than 60 minutes.