Voters are likely to have the final say on the planned purchase of 22 fighter jets for the Swiss Air Force. Parliament approved the deal last year, but opponents have now collected enough signatures to have a nationwide ballot.
Two separate groups said they collected more than 100,000 signatures, twice as many as necessary to challenge a parliamentary decision.
They were handed in to the Federal Chancellery on Tuesday.
The purchase of the jets is too costly and unnecessary according to a committee of centre-left politicians. It said the existing fleet of FA/18 aircraft was sufficient to defend Switzerland’s airspace.
A separate group of centrist politicians for its part, added that it was not the right time to buy new aircraft for CHF3.1 billion ($3.4 billion) from the Swedish Saab company.
However, the centre-right Radical Party said the opponents were undermining Switzerland’s air force and national security.
No date for the vote has been set.
Last September, parliament approved the purchase following five years of heated discussions.
swissinfo.ch and agencies