Police are clearing Black Dam roundabout after a crash between a Jeep and a Ford Focus.
It was reported to have happened just before 12pm on the A339 ringway.
Police have cordoned off part of the roundabout while the road is cleared.
At the scene, a black Ford Focus and a bronze car were being recovered.
Traffic remains free-flowing with minor disruption, with drivers diverted.
A spokesman for Hampshire Constabulary said: "We were called at 11.56am with reports of a collision on the Black Dam roundabout.
"A Ford Focus and a BMW were involved.
"No injuries have been reported at this time.
"The road is currently blocked, however recovery is being arranged for the two vehicles."
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