Spanish air traffic controllers voted yesterday to strike over government changes to their work hours that reduce their overtime pay, a move that could disrupt flights at the peak of the tourist season.

A total of 92 per cent of the country’s 2,300 controllers with a right to vote cast ballots and almost all, 98.25 per cent, voted in favour of the strike, the Union of Air Traffic Controllers (USCA) said in a statement.

The date for the strike is expected to be announced today but since the union must give a 10-day warning, the earliest it could come is mid-August, the busiest time for the country’s key tourist industry.

USCA said a strike “was the only alternative to denounce their labour conditions and, consequently, air traffic security.”

The controllers, who are employed by state-run airport management firm AENA, are angry over a government decree on working conditions announced last week which would reduce rest periods and cut generous overtime benefits.

Their contracts stipulated a working year of 1,000 hours, which most of them topped up with a further 600 hours of overtime, that was paid at triple rate.

Under the new rules approved by the government last week, the controllers are now obliged to work 1,600 hours at a normal wage, which still gives them an annual salary of €200,000 compared to €350,000 previously.

Earlier yesterday Transport Minister José Blanco said he saw “no reason” for a strike and called on the controllers to adopt the new rules “without delay.” He also vowed to maintain minimum services during the walkout.

During recent railway sector strikes, minimum services has meant maintaining between 50 and 75 per cent of traffic.

The government has called the “millionaire salaries” enjoyed by the controllers “incomprehensible privileges” at a time of austerity to slash Spain’s public deficit, the eurozone’s third-highest after Greece and Ireland.