Ryanair plane taking off in Palma. | Paul Hanna

Pilots' unions in five countries have informed Ryanair that they will take strike action this summer if there is not a "substantial change" to cabin crew working conditions.

Belgian, French, Italian, Portuguese and Spanish pilots' unions are warning of strikes because of "precarious" working conditions. In Spain, the SITCPLA and USO unions are demanding the application of basic labour rights, including an end to pay which they claim is below the minimum wage.

A statement from the USO denounces alleged "irregularities committed by Ryanair in the management of its personnel and attacks against the rights of its workers". The union maintains that these include cabin crew working without access to water on planes. This is despite the employment inspectorate in Spain having sanctioned the airline.

The unions in the different countries also point to the need for the airline to adopt various national laws and social norms in countries where it operates and to "recognise the rights of workers to organise themselves in unions of their choice and to participate in collective bargaining".