West Sussex Highways are reporting that the road has re-opened in both directions after highways teams worked through the night.
A total of 3,000 square metres of carriageway were resurfaced.
The road was been closed in both directions; northbound from Ashington B2133 to the Partridge Green junction with the B2135, and southbound between the Buck Barn crossroads and Dial Post.
A lorry carrying a refrigeration trailer filled with milk was involved in an accident which saw both milk and diesel spilled onto both carriageways just after midnight.
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