Hillingdon Council's Major Applications Planning Committee approved proposals for a re-development in October 2014. It is set to bring new homes, a Cineworld complex, an Asda supermarket and several restaurants to South Ruislip.
After approval was granted, Sainsbury's requested that the decision be subject to a judicial review, arguing that the council had been inconsistent with its decision-making process and had misapplied planning policy.
He said: “The fact that the judge made no criticism of the council's handling of the application speaks highly of the skill and judgement of our planning department.
“Sainsbury's clumsy efforts to delay progress on this scheme were little more than a time-wasting exercise. At long last the way is now clear for work to begin on providing new homes, shops and leisure facilities for the borough's residents."
Toby Baines, chairman of Citygrove - the developer behind the new complex - “can't wait” to get started as soon as possible.
He said: “In response to Sainsbury's, sense has prevailed and we're delighted. Let's hope this is the end of a long and expensive road. It's something that we believe shouldn't have needed to have got this far."
Citygrove say they will be remobilising and re-engaging its whole team to get work started, although they cannot yet give a solid start date.
“The only thing preventing this project from happening has been J Sainsburys using the legal system," Mr Baines added. "We're already six months behind schedule so I want to get going and I want to catch up fast.
“The good news is that the building contractors are relatively quick but it will take about 56 weeks from start to finish before the operators then go in and fit. It will be seriously fast-tracked.”
Citygrove, as well as Hillingdon Council, have shelled out a large sum of money to battle against J Sainsbury's in the courts over the development of a site which has been derelict since 2004.
A previous estimate of the cost to the taxpayer was estimated at £200,000 for Hillingdon Council's legal costs.
Mr Baines added: “It's been a very expensive legal time for us, we've got massive legal bills relating to the delay caused by J Sainsbury's. It runs into hundreds of thousands of pounds.
“The residents of South Ruislip wanted the leisure facility for the town, the housing, the supermarket and the choice of restaurants. It's ridiculous that this site is in a prime London borough and has been sitting derelict and vacant for over 10 years.”
South Ruislip Residents' Association (SAA) had one of its quarterly meetings the day of the judicial review announcement, which it said was met by “applause”.
Chairman Sid Jackson said: “We look forward to enjoying the complex in the future although we do have concerns about traffic levels."
A Sainsbury’s spokesman said: “We are clearly disappointed with the outcome, but respect the Judge’s decision.”
Sainsbury's has a store near to the development, in Long Drive, which it has had planning permission to double the size of since 2006, but has not acted upon.
"We have planning permission for a replacement store and are now considering our future options," the spokesman added.