International Airlines Group, formed by the merger of British Airways and Iberia, may struggle to persuade a rival airline to buy a stake currently owned by a troubled Spanish bank, despite signalling that it would be open to such a deal.

In an interview with Spanish financial newspaper Expansion, IAG chief executive Willie Walsh said investors were interested in Spanish lender Bankia's 12 percent stake and that the company is open to other airlines as shareholders.

Bankia is under pressure to sell corporate shareholdings since asking for a 19 billion euro ($24 billion) bailout, the largest state rescue in Spain, last month. Its stake in IAG is worth 419 million euros ($527 million) at current prices.

“The list of candidates that have the firepower to buy that stake is very short,” said Gerald Khoo, an analyst at Espirito Santo Investment Bank.

European airlines such as Air France-KLM and Lufthansa are struggling under the weight of soaring fuel prices and high taxes, while U.S. partner American Airlines has been in Chapter 11 since November.

“Bankia's stake will have to be sold on the market to institutional investors. Other airlines aren't in a position to buy it, especially when it could face big regulatory hurdles,” an airline analyst in Spain, who asked not to be named, said.

Last week, Britain's Office of Fair Trading (OFT) ruled that Ryanair's ownership of a minority stake in Irish rival Aer Lingus threatened competition in the British market and recommended sanctions.

However, one option could be Abu Dhabi's fast-growing Etihad Airways, which bought a 4 percent stake in Virgin Australia this month. Etihad has completed four overseas deals since December in its drive to compete with rival Gulf airlines.

“There are investors interested in replacing Bankia, and in my opinion it is not a question of if, but when they are going to sell,” Walsh told Expansion.

He said he was open to having other airlines as shareholders as long as they remained “neutral”, adding that there was no strategic value in having the Spanish government - which holds 12 percent of IAG - as a stakeholder.

IAG was formed by the merger of British Airways and Spanish flagship carrier Iberia in 2010. Bankia, through savings bank Caja Madrid, had been a leading shareholder in Iberia since its privatisation in 2000. - Reuters