Queues of more than a mile long built up on the southbound A3M following a three car crash.
The accident happened just after 7am today, just past Queen Elizabeth Country Park, close to the Clanfield turn off. Both lanes are still blocked off after a car went into the central reservation.
It is believed it was then struck by another two cars.
A small oil spill means the road will be closed until it is cleaned up leading to a nightmare for Monday morning rush hours commuters.
No injuries have been reported but long delays are expected.