More than half of people who took parts in consultations on the Rudmore, Portsbridge and Spur Road roundabout schemes backed efforts to make them safer to navigate and reduce congestion.
Cabinet member for transport Lynne Stagg said: ‘It's really important to improve safety and make bus journeys more efficient at these key roundabouts, so it's good to see many residents and business share their views about these plans.
‘We'll continue to develop these schemes and work with our partners on this project to make travel safer and swifter for people who travel in Portsmouth. ’
Consultation on the Transforming Cities Fund-funded project, which is being managed by South East Hampshire Rapid Transit, took place in August and the council said construction could start as soon as spring next year.
This is dependent on a formal traffic regulation order being approved.
Support for improved cycling infrastructure was highest for the Spur Road roundabout at 70 per cent of responses agreeing with the concept compared to 59 and 54 per cent respectively at Rudmore and Portsbridge roundabouts.
Among the measures proposed as part of the schemes is the widening of the northbound access to the motorway at Rudmore roundabout and changing its layout to allow two lanes from the A3 at Stamshaw Road onto the M275.
A series of new traffic islands are proposed for Portsbridge roundabout and improvements to pedestrian and cycle access at Spur Road.