AFP - The Spanish government on Friday curbed "millionaire salaries" enjoyed by the nation's air traffic controllers, calling their high rates of pay and benefits "incomprehensible privileges".

Public Works Minister Jose Blanco said salaries for the country's 2,300 air traffic controllers, who are employed by state-run airport management firm AENA, would be cut to the average level in the European Union.

"It is not acceptable that a public firm pay millionaire salaries to its employees while the government demands austerity to the rest of Spaniards," Blanco told a news conference after the measure was approved at a weekly cabinet meeting.

"We cannot continue to pay for this public service double what is paid in the rest of Europe," he said, adding the high salaries and other benefits which the controllers enjoyed were "incomprehensible privileges".

According to figures released by the transport ministry last week, 135 controllers earned more than 600,000 euros (830,000 US dollars) per year while 713 earned between 360,000 and 540,000 euros.

By comparison Prime Minister Jose Luis Rodriguez Zapatero earns just under 92,000 euros a year while the average salary in Spain is just over 18,000 euros per year, according to government figures.

In addition, the controllers can retire at the age of 52. The Spanish government announced last week it plans to raise the retirement age from 65 to 67 to cope with a rapidly ageing population.

The news that many controllers earned more than the prime minister caused outrage in the recession-hit country, where the unemployment rate in nearly 20 percent, the second-highest rate in the EU.

In an editorial, centre-right daily newspaper El Mundo called the salaries they earned "scandalous".

Blanco said the law approved by the cabinet on Friday would return the sector to Spain's public airport authority AENA.

"Currently it is the employees who manage and organise this public service," he said, referring to a 1999 agreement which granted air traffic controllers autonomy and control over their salaries.

The union representing the controllers said it would take legal action to defend their existing collective agreement.

Despite their high pay, the controllers staged a work-to-rule protest at the end of 2009 which caused flight delays during the busy Christmas period.

Last week the Spanish government announced spending cuts of 50 billion euros aimed at slashing its public deficit to the EU limit of 3.0 percent of total output by 2013 after the shortfall mushroomed to 11.4 percent last year.