Spanish airline Iberia has received a second takeover approach from a private equity-led consortium, valuing the business at about 3.7bn euros ($5.5bn).
Iberia is market leader in flights between Europe and South America
The indicative offer has come from a group headed by Madrid-based Gala Capital and a number of Spanish banks.
It is higher than the existing $5.01bn bid from Texas Pacific Group, which is being backed by British Airways - itself a shareholder in Iberia.
Analysts said Gala's intervention could force the Texas group to raise its bid.
Iberia disclosed details of the latest approach in a regulatory filing, adding that the Gala consortium had asked to obtain access to the airline's books to assess its financial position.
Iberia made no further comment on the development, which could trigger a bidding war for one of Europe's most respected airlines.
Trading in Iberia shares was briefly suspended after the news emerged, but they were later trading up more than 4% by mid-afternoon.
Iberia's board is likely to discuss the approach at its next scheduled meeting on 22 November.
Besides British Airways, Iberia has also attracted interest from Air France and Lufthansa but many would-be suitors are concerned about the cost of a deal at a time when financial conditions in the industry remain tough.
One analyst said Gala's approach could deter other would-be bidders.
"With the bid level at 3.90 euros (a share), that's a very dissuasive offer for anyone who might be sniffing around on the outside," said Penny Butcher, from Morgan Stanley.
"TPG seemed to have had a hard time getting a bid together and from that I infer that it was on the high side for them. This may force their hand."
Europe's fourth-largest airline, Iberia carried almost 28 million passengers last year.