Newhaven swing bridge was 'jammed' and causing traffic earlier this morning but is now open.
The fault caused the A259 to close, according to reports.
Police said at 9.17am that the issue was not likely to be fixed for another hour.
Brighton and Hove bus services were diverting via the A26, A27, Falmer Road and Rottingdean in both directions.
However just before 11am the bus service announced that the bridge had reopned, although delays remained.