PLANS to extend a Bicester supermarket by a third before it has even opened its doors have been recommended for approval.

The supermarket is currently under construction as part of the £70m town centre redevelopment, which includes shops, restaurants and a cinema, and is due to open this summer.

Sainsbury’s wants to expand the store by 30 per cent – from 4,842 sqm of sales floor space in its original plan – to 6,292 sqm, to compete with new Tesco plans.

Tesco’s new store would have 5,151 sqm of sales floor space.

The move came after Tesco and Bicester Village unveiled joint plans to extend the designer shopping centre into Tesco’s current site in Pingle Drive, and open a new store, double the current size, across the A41.

Tesco’s plans were approved last month but have been referred to the Secretary of State, who has yet to decide whether to call them in.

At the time Sainsbury’s said it might stop work to fit out its store if the Tesco plans were approved. This week the firm said it was still “reviewing its position”.

The Sainsbury’s expansion would involve adding an additional 1,450sq metres of sales space in a mezzanine area and would not involve any exterior changes to the building.

Its Banbury store has a sales area of 6,001 sqm.

There would be no extra car parking.

A Sainbury’s spokesman said: “While we are still reviewing our position, our application to extend the mezzanine floor within our store has been submitted to encourage more people to use the town centre and respond to new out-of-centre developments.”

One letter of objection was received from a resident in nearby Hunt Close, who said the supermarket already dominated the development and would cause other retail outlets to close, that it would increase traffic, light and air pollution, and the development was of a low eco standard.

Neither Oxfordshire County Council’s highways department or Bicester Town Council raised any objections.

Cherwell District Council planning officer Bob Duxbury said in a report: “There are no physical changes proposed to the external appearance of the approved building.

“There will be some increase in traffic generation but this is not considered to be at a level that would impact upon the residential amenity of nearby properties.”

Councillors will decide on Thursday whether to approve the application.