"If Ryanair does not change this attitude, the only alternative that we have is to work towards taking the Portuguese example and replicating it in a strike at the European scale," said Fernando Gandra of the SNPVAC union, the main organisation representing airline cabin crew in Portugal.

After assessing the impact of the current strike, he said, union officials would sit down with colleagues from its counterparts in other European countries to discuss the issue.

Gandra, who was speaking after a news conference in Faro attended by representatives of the Italian union for cabin crew, said that SNPVAC members had been the target of "constant bullying" by Ryanair, with "several examples of intimidation and harassment".

The union had called the three-day strike to demand that the company observe Portuguese law, specifically relating to sick leave and parental leave, as well as calling on it to restore penalties levied on employees who failed to meet targets for in-flight sales.

According to Gandra there are similar problems with Ryanair operations in other European countries. He said that he hoped the company "learns a lesson" from its brush with its workers in Portugal.

The SNPVAC official praised the "great courage" of cabin crew in Portugal who had taken the first such strike to affect Ryanair in its 30 years of existence.

Ryanair announced earlier that "just eight of the first flights of the day were cancelled" out of a total of 170, stressing that "the great majority of cabin crew" based in Portugal were working "as normal".

However, the union has accused the company of rejigging its rosters so that crew based outside Portugal could work on flights that would have been staffed by Portuguese colleagues - so alleedly flouting local laws governing strikes.