Stansted Airport was put up for sale yesterday after its owner BAA finally gave up a three-year battle against the Competition Commission which ordered the sell-off in March 2009.
The decision is a blow to BAA's chief executive Colin Matthews who has fought to avoid a forced sale of the airport in the current economic climate.
The sale, which could raise at least £1bn, is expected to attract attention from rival airport operators and private equity groups. Manchester Airport Group has been tipped as one of the frontrunners to buy the business.
Stansted is London's third airport and the UK's fourth-busiest, handling some 17.5 million passengers a year
BAA has already been forced to sell Gatwick for £1.5bn and Edinburgh airport for £800m last April as result of the Competition Commission inquiry.
Both were bought by Global Infrastucture Partners, which also owns City Airport and is itself owned by Credit Suisse and General Electric.
Stansted's traffic numbers have been falling since 2007 and last month's figures from BAA showed them down another 4.6 per cent so far this year.
The airport has been losing traffic as low-cost airlines and tour operators cut capacity to reflect slowing demand.
BAA said yestrday that Stansted's bottom line profit was £86.6m in 2011.
The company has been set a deadline by the Competition Commission to complete the sale of Stansted, but said that date remained confidential because it is commercially sensitive.
The most recent court hearing centred on BAA's claim that there had been a material change in circumstances since the Competition Commission first ruled on Stansted.
A BAA spokesman said: "We still believe this to be the case. There isn't a single airline which flies out of Stansted which operates out of Heathrow. But the legal advice was that we should not challenge the Supreme Court.
"That does not alter the fact that we are being forced to sell a prime asset at the bottom of the market."