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