Manchester Airports Group is being tipped as a possible £1 billion bidder for Stansted.
Despite lengthy opposition to the enforced sale of the Essex airport by the Competition Commission, owner BAA is expected to have to put Stansted up for sale later this year.
Speculation is surrounding Australian investment firm Industry Funds Management taking a stake in MAG to help fund a bid for Stansted, according to the Sunday Times.
The deal with IFM is conditional on MAG making a play for Stansted and the investment group would gain a 35% stake in a joint venture holding the assets of both airports.
MAG, which includes Manchester, East Midlands, Humberside and Bournemouth airports, handled 23 million passengers last year against 18 million at Stansted