Spanish airline Iberia has said some 1,300 flights will be cancelled this week as workers begin a second round of strikes in protest at the loss-making company's plans to lay off almost a fifth of its workforce.
The government has ordered that a minimum service should remain, meaning that 85% of long-haul flights, 62% of medium-haul and 47% of domestic flights are guaranteed.
Unions representing most Iberia workers, but not pilots, called strikes between February 18 and 22, March 4 and 8 and March 18 and 22.
A demonstration will be held at Madrid's Barajas Airport on Monday.
International Airlines Group, which owns British Airways and Iberia, lost 923 million euros (£799 million) last year on restructuring costs and writedowns on the value of Iberia.
Iberia last month said it planned to cut 3,807 jobs.