Drivers are being asked to avoid the Eastern Road this weekend while northbound lanes are closed as part of ongoing maintenance work.
The Eastern Road will be closed northbound between Anchorage Road and the A27 from 7.30pm on Saturday, 8th September, and 3pm Sunday, 9th September.
Diversions will be in place via Norway Road and London Road but drivers are being asked to plan journeys in advance, allow extra time and avoid the area if possible by using alternate routes such as the M275 to get out of the city.
Cyclists and pedestrians will be unaffected as the pavement and cycleway are open as usual.
The road closure is to enable ongoing essential maintenance work on the bridge that carries the Eastern Road over the creek.
Normally as much maintenance work as possible is done at night but unfortunately, due to the time it takes for the work to be done and road surface restored the road has to be closed during daytime.
The work has been scheduled to minimise disruption as much as possible by avoiding the school holidays and the closure will not begin until the roads have cleared from football traffic leaving Fratton Park.
Steve White operations manager for Colas who manage the roads for Portsmouth City Council, said: "This work is part of our ongoing maintenance for the bridge and, as always, we are doing everything we can to minimise disruption to residents and drivers. During the work drivers should avoid the Eastern Road where possible and use other routes. People should plan their journeys and expect some delays. We are very sorry for the inconvenience and disruption this will cause people and grateful for their patience and co-operation."