Europe's biggest budget airline averted widespread strikes before last Christmas with a last-minute u-turn on union recognition, but has since struggled to reach agreement on terms in some countries.

It has found most success in Italy and followed up a deal in March to recognise pilots by signing its first crew union recognition agreement with the ANPAC and ANPAV unions, which it said made up around 20 percent of its total cabin crew.

"We are making good progress with other cabin crew unions across Europe and we hope to sign more recognition agreements with both pilot and cabin crew unions in the coming weeks," Ryanair Chief People Officer Eddie Wilson said in a statement.

Spanish pilots' union SEPLA broke off its recognition talks last month while the airline has experienced minor disruption in Portugal due to industrial action and faces a threat of strike action in its home market of Ireland.

The union representing Ryanair pilots in Britain, the only other market where a recognition deal has been struck, also threatened possible strike action last week unless the company implements a transparent system to manage promotions and transfers. The airline operates in 37 countries.

(Reporting by Padraic Halpin; Editing by Adrian Croft)