Virgin America Inc., the airline backed by British billionaire Richard Branson, has reportedly received takeover bids from JetBlue Airways Corp. and Alaska Air Group Inc.

Virgin America, based in Burlingame, California, had recently started working with a financial adviser as it explored the prospect of a sale. Asian airlines have also indicated they might want to buy the U.S. budget carrier, although the foreign companies would have to partner with an American bidder as required by U.S. law.

A person familiar with the takeover discussions spoke with Reuters this week on the condition of anonymity, as the sale process is confidential.

Virgin America and Alaska Air did not immediately return requests for comment. A spokeswoman for Jet Blue said the airline wouldn’t comment on “rumors and speculation.”

Shares in Virgin America (NASDAQ:VA) jumped around 10 percent last week after Bloomberg first reported news of a potential sale. The company’s stock rose nearly 2.5 percent Tuesday morning to $38.63 after market opening. The S&P 500, by contrast, was down 0.32 percent.

Virgin America, which flies to destinations throughout the United States and Mexico, started offering flights in 2007. In the last year, the low-cost carrier has faced steep declines in unit revenue — the airline’s total revenue divided by available seat miles — as larger rivals add more seats to gain market share and take advantage of cheaper fuel prices.

Mega-mergers among bigger U.S. airlines over the last decade have reduced the industry to four key players: American, Delta, United and Southwest, which control more than 80 percent of the market.

By linking with another airline, Virgin America could add more flights and gain a competitive edge, Reuters reported.

Analysts told Reuters that a deal makes sense in particular for New York-based Jet Blue, which hasn’t fully expanded into the U.S. West Coast. Both carriers fly the same type of aircraft, meaning JetBlue’s pilots and maintenance crews wouldn’t need to retrain to learn how to operate Virgin America’s planes.

Adam Hackel, an analyst with Sterne Agee CRT, told Reuters the prospective buyers could benefit from Virgin America’s corporate accounts with U.S. technology giants including Facebook Inc. and Google’s parent company Alphabet Inc. Virgin America this month launched a new route from San Francisco to Denver expressly to connect Silicon Valley entrepreneurs with Colorado’s brimming innovation economy.

Branson owns a 22 percent stake in Virgin America through a hedge fund and the Virgin Group, the U.K. venture capital conglomerate he founded. Branson’s investment in the airline is restricted by U.S. foreign investment rules.