Plans to bring Cambridgeshire County Council’s multi-million pound headquarters to a site at Alconbury Weald are running to programme, the authority has said.

The new civic hub is expected to save the council £46.5million over the next 30 years by replacing the current Shire Hall headquarters which stands on a valuable site in central Cambridge.

About 350 staff would work at the new hub, which is likely to cost the best part of £20million.

The council's commercial and investment committee approved the move at a meeting in March after whittling down a number of potential sites in the county.

It hopes to start work towards the end of the year and have the building ready for completion at the end of 2020.

A council spokesman said: "We are in programme. A planning application is to be determined."

The planning application is being considered by Cambridgeshire County Council itself and follows a decision by the authority to move to a smaller, more flexible building at Alconbury.

The curved, two-storey 4,219 sq m civic hub includes office space, a multi-function meeting area capable of holding full council meetings, a staff "breakout" area and parking for cars and bikes.

If it gets the go-ahead the building would be split asymmetrically on either side of a landscaped courtyard with the smaller west wing dealing with public contact and the larger east wing accommodating staff offices.

It would face the listed Watch Tower building, where wartime activities were masterminded.

Huntingdonshire District Council has raised concerns about the impact proposed siting of the hub would have on the Watch Tower, which is being restored.

Stukeleys Parish Council welcomed the county council's decision to move to Alconbury Weald as a recognition of the growing importance of the site.

But it raised concerns about the "ambitious" travel plan assumptions which led to fears that vehicles would park in the industrial area through a shortage of space, especially before an enhanced sustainable transport structure was in place.

A linked planning application, on land adjacent to the iMET skills centre, has been made to Huntingdonshire District Council by Urban and Civic, which is behind the conversion of the former airfield into a residential business centre.

It is for the approval of appearance, layout, landscaping, access, drainage and an electrical sub-station.

The Urban and Civic application said: "The application is for infrastructure to serve an area of the enterprise zone, adjacent to the proposed civic hub building which is the subject of a separate but related planning application by Cambridgeshire County Council.

"The works build upon and integrate with the existing network of landscaping, drainage and highways infrastructure which have been approved under key phase one submissions."

The county council said the Alconbury development was part of its plan to move away from its Shire Hall base - the future of which remains unclear - and locate services closer to communities by making better use of its own buildings and those of key partners.

Some county councillors had questioned the move, describing it as a white elephant, with the future shape of local government becoming uncertain.