LONDON (Reuters) -Turkish Airlines is exploring making a bid for a minority stake in Air Europa, the latest carrier to express interest in the Spanish airline, according to two sources with knowledge of the deal, with binding bids due in the coming weeks.

Interested investors have been asked to submit binding bids by early July, one of the sources and two more said. The sources declined to be identified because the terms are confidential.

Turkish Airlines' consideration of a bid is significant as there are few examples of carriers outside Europe buying shares in players in the region. The interest has been reported by Spanish online newspaper El Espanol. The deadline for binding bids has not previously been reported.

Air France KLM and Lufthansa are also in talks with Globalia, the holding company of the family Hidalgo that founded the company, about buying a stake, Reuters reported previously.

The airline makes just over a quarter of its revenues from Europe. It has a codeshare agreement with Air Europa.

Turkish Airlines did not immediately respond to requests for comment, while its shareholder Turkey's Wealth Fund declined to comment.

A representative for Globalia and the Hidalgo family said they did not want to comment on an ongoing operation because of confidentiality issues. Lufthansa declined to comment. An Air France-KLM spokesperson said the airline is interested in reinforcing its longstanding cooperation with Air Europa.

NEXT PHASE OF LONG PROCESS

Binding bids would mark the next phase of a prolonged sale process as Air Europa seeks to raise cash to repay a government loan granted during the pandemic. A previous plan had aimed for binding bids in May, two of the sources said.

The process has faced delays due in part to disagreements between members of the Hidalgo family and concerns from interested airlines on the structure of the deal, according to the two sources and a fourth one said.

The interested parties are working with advisers to structure bids in the hope that buying a minority stake of about 20% may put them in a better position to take control of the airline in the future, the two sources added.

Some potential suitors have expressed concern over a lack of clarity about how they may be able to do that, according to the fourth person with knowledge of the talks.

Last year, BA-owner IAG which has a 20% stake, abandoned a deal to take full ownership of the airline after regulators raised issues over competition given its ownership of Spanish carrier Iberia. It also owns Vueling and Aer Lingus.

Pressure has mounted on airlines to consolidate in Europe to better compete with major global rivals from the United States and the Middle East. Many are focusing on the most popular routes in southern Europe as a target for expansion.

Air Europa flies within Spain and between Madrid and large cities in Europe and Latin America.