National Highways warned last week that works were due to take place on A27 westbound between A24 near Worthing (east) and A24 near Worthing (west).
A closure is now in place between the Grove Lodge roundabout (Broadwater) and the Offington roundabout.
These are the junctions with the A24 South and the A24 North.
A National Highways notice read: “Road repairs are planned. Expect disruption everyday between 8pm and 6am from 18 April 2024 to 18 May 2024.”
A photo taken on Tuesday (April 23) shows heavy traffic leading up the Offington roundabout.

1. A27 roadworks
Motorists have been told to 'expect disruption everyday' after A27 repair work began Photo: Eddie Mitchell