Switzerland began seeking replacements for its ageing fleet of fighter jets more than a decade ago, but the issue has become caught up in a political battle in the wealthy Alpine nation.

In 2014, the country looked set to purchase 22 Gripen E fighter jets from Swedish group Saab, only to see the people vote against releasing the funds needed to go forward with the multi-billion-dollar deal.

But Bern has not given up on its quest to boost its fleet, with the government warning that the country's F/A-18s will reach the end of their lifespan in 2030.

"If they are not replaced in time, Switzerland will no longer be in a position to protect and even less defend its airspace by 2030," the government said earlier this year.

Switzerland also has an even older fleet of F-5 Tiger jets, built by US group Northrop Grumman, but they are not equipped for night flights.

If Switzerland has to rely on them, they will only be operational "during the day and only when there is good visibility," the government said.

- 'Luxury' fighter jets -

To remedy the problem, the government has proposed to release up to 6 billion Swiss francs ($6.1 billion, 5.1 billion euros) for a new fleet of jets.

After several weeks of debate, both chambers of the Swiss parliament, which together tilt to the centre-right, approved the plan Friday.

The leftwing Socialist Party however balked at what it considered a far too high amount, insisting that "Switzerland does not need luxury fighter jets."

It insisted the small land-locked country, which has not seen armed conflict for centuries, had no need for fancy jets, and should opt for lighter, less expensive aircraft that "will guarantee the security of Switzerland's airspace, and at the same time protect the interests of the taxpayers."

As part of Switzerland's famous direct democratic system, the party launched a campaign to gather enough signatures to put the issue to a referendum.

They are expected to succeed, and the referendum would likely be held next September, according to the ATS news agency.

The vote would however only touch on whether or not the people are in favour of replacing Switzerland fighter jet fleet.

If they agree, the choice of jet would fall to the government.

apo/nl/pld/pma

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