Singapore Airlines (SIA) has confirmed it is in talks to sell its 49% stake in British carrier Virgin Atlantic.
The interested parties have not been named, but Reuters has reported that Delta Air Lines had held recent talks to buy SIA's stake.
Delta, the second-largest US airline by operating revenue, has been looking to acquire a stake in Virgin Atlantic for more than two years in an effort to expand its access to London's Heathrow airport, sources said.
Previous talks broke down over price and other issues, and there is no guarantee that the recent discussions would result in a pact, Reuters quoted the sources as saying.
The European Union requires that EU carriers be under European control, meaning Delta would need to involve an EU airline if it sought majority control.
Delta has been considering ways to partner with Air France-KLM, which could take an additional stake in Virgin and allow the carriers to acquire majority ownership. Virgin founder Sir Richard Branson owns 51% of the airline.
Delta has made clear that it would like to expand at Heathrow, a lucrative airport for prized corporate passengers where landing slots are generally hard to acquire.
Virgin is the second-largest carrier at Heathrow after British Airways.
Sir Richard, who set up Virgin Atlantic in 1984, has been weighing the airline's future for some time and two years ago appointed Deutsche Bank to examine offers.
"We are always talking to many airlines on a number of different matters but we never comment on the details of these discussions," a Virgin Atlantic spokeswoman said. Delta declined to comment.
Heathrow, Europe's busiest airport, is operating at close to full capacity after the Government blocked its expansion in 2010.