Work on Travel Ipswich re-starts next week after the “Christmas truce” for town centre shoppers – but there is still no clear idea when it will be finished.

The final design of the Queen’s Street redevelopment has still to be unveiled – and it is not known when all the traffic lights will be linked to a computer control scheme in a bid to ease the traffic chaos that has gripped the town over recent months.

The next work on the controversial scheme are set to be begin in the New Year, with three of the town’s major junctions involved.

Next Monday work will begin upgrading the traffic lights at the Spring Road and Cauldwell Hall Road junction and is expected to last around five weeks.

Further traffic control work will take place at the Hadleigh Road junction for three weeks, starting on January 12. Drivers will only be able to access Sainsburys from the town end of Hadleigh Road during that time.

A third series of traffic flow upgrades will be installed in Norwich Road, Valley Road and Chevallier Street. Pavements and roads will also be resurfaced, as well as an additional crossing outside Westwood Court being added. Work is set to begin in February for 12 weeks.

Further work at Majors Corner is also expected, although dates to start it are yet to be announced.

Graham Newman, Suffolk County Council transport spokesman, said: “We have completed a significant amount of work during the past year, and we are now getting to the point in the project where we can see how the transport infrastructure is allowing us to prepare for growth on our road network.”

But the scheme, which began in the middle of 2012 after Suffolk County Council received a major grant from the Department for Transport, has come under heavy criticism.

The project was due to be completed by Easter this year, but contractors were unable to keep to the schedule.

Concerns that the £21 million budget may have been exceeded had also been raised.

Mr Newman added: “With the parts of the scheme already completed, alongside the new traffic management system and promotion of alternative travelling choices, including using the bus, walking and cycling, we can help alleviate some of this disruption now and in years to come.”