THE A419 will close overnight for 12 weeks beginning on Tuesday evening, with traffic being diverted through Swindon.

Highways England is beginning a major maintenance programme of the busy dual carriageway that links the M4 along with the A417 at Cirencester to the M5 at Gloucester.

The project will be split into two six-week periods and will see full carriageway closures on parts of the Cotswold artery from 8pm to 6am.

The first set of closures, which begin tomorrow evening, will involve highway maintenance work such as grass cutting, drainage, channel sweeping and road markings.

This will start at junction 15 of the M4 and progress on to Commonhead. The work will then be completed section by section up to Cirencester and continuing onto the A417 M5 junction 11a.

But there will be some relief for drivers, especially during the busy tourist season of the summer.

There will be a two-month break between the roadwork periods, from mid-June to the end of August, which avoids the Royal International Air Tattoo which is being staged at RAF Fairford between Friday, July 8, and Sunday, July 10.

There will also be no closures in place over weekends or on any bank holidays.

The second six-week programme of work will start after the August Bank Holiday and will concentrate on resurfacing and patch work – which highways bosses hope to have completed by the end of October.

While Highways England engineers are carrying out their first phase of work between the M4 and the Commonhead junction, drivers will be directed along the M4 to junction 16 to leave instead before being directed back towards the A419.

When engineers move on to the section between Commonhead and the White Heart roundabout drivers will be sent along the A259 past the Great Western Hospital to Drakes Way where they will continue on past Greenbridge and then rejoin at the White Hart roundabout.

When they move north again and are working between the Blunsdon Turnpike and Cricklade drivers will have to use the B4553.

A spokesperson for Highways England said the overnight closures were being put in place to ensure the safety of not only the workforce, but also drivers.

They said: "Agreed diversion routes will be in place during the various closures, together with advanced signage on the network detailing times and dates.”

For information and live traffic updates, visit highways.gov.uk/traffic-information.