Manchester Airports Group's commercial property business MAG Developments, which is behind plans for the £800m scheme, is in talks with an office occupier about signing up for 65,000 sq ft, and an advanced manufacturer which wants 200,000 sq ft.

The news comes as plans for Airport City move forward ahead of formal designation of the enterprise zone later this year.

Business leaders and politicians are likely to press for the enterprise zone to extend beyond the 150 acres already planned.

The government's enterprise zones will offer special tax advantages and a simplified planning system in an effort to lure businesses.

The Airport City Enterprise Zone, announced by the government in the spring Budget, is intended to create up to 15,000 jobs over the next 20 years.

John Atkins, managing director at MAG Developments, said: "We could be looking at between three and four million sq ft of new commercial floorspace at Airport City, including offices, distribution space, hotels and advanced manufacturing.

"We are carrying out a market analysis now to decide what kind of buildings would be most suitable. We are talking to government to determine how the simplified planning zone will work."

It is not yet clear how the site will be developed. Around 90 per cent of the land is owned by MAG Developments or by Manchester city council. The project could involving selling plots to other developers.

"It is yet to be determined how this development is done and we are looking at options to deliver it," said Mr Atkins.

"This is a 15-20 year project potentially, and it’s a very big step for the company."

MAG Developments has been gearing up for growth. Last week it made a new appointment to its development team, ahead of an increased focus on this area of the business across its four UK airports over the next few years.

Neal Biddle joins as development manager and will support the delivery of the group’s development portfolio at Manchester, East Midlands, Humberside and Bournemouth airports, reporting to property development director David Roberts.

Over the last 12 months, Manchester-based MAG Developments has invested capital into a number of development projects across the UK.

These include a £2.6m, 36,000 sq ft facility pre-let to City Link and the speculatively built Cirrus Court, both at Bournemouth Airport. Other projects include a 216-bed, £22m four-star hotel at East Midlands Airport.

MAG Developments is also looking to develop further hotel opportunities within the next 12 months, specifically at Bournemouth Airport where the imminent completion of new terminal buildings as part of a £50M infrastructure investment has resulted in a need for its first ‘on site’ hotel.

MAG Developments’ £325m investment portfolio comprises over 200 properties across 5,000 acres, serving more than 850 companies.