The Dutch opposition Labor Party on Tuesday announced that it would withdraw its support from the purchase of F-35 Joint Strike Fighter aircraft. With other left-wing parties, the centrist Democrats and the nationalist Freedom Party, it has a majority to block acquisition of the plane.

The opposition parties cited budget concerns as reason to end participation in the program. However, many have opposed the F-35 purchase from the start.

The Netherlands joined the Joint Strike Fighter project as a Level 2 partner in 2002 and pledged to invest $800 million in the development of the plane that is set to replace the Netherlands’ aging fleet of F-16s.

Labor, though wary of the purchase, agreed in 2007 in government with Christian Democrat parties to buy two test planes before committing to acquire a total of 85. That number was expected to drop even after the conservatives formed a coalition with the liberal party in 2010 as Lockheed Martin’s costs of developing the F-35 have significantly mounted. The Netherlands could buy as few as 42 planes instead.

When the country decided to enter the project in 2000, it expected a total cost per plane of €35 million. The Dutch Defense Ministry now estimates a price of up to €61.5 million per plane.

The Dutch Royal Air Force has operated F-16 fighter jets since 1979. Sixty-seven are still in service. Eighteen were most recently sold to Chile in 2010. The remaining aircraft are slated to be replaced in 2015 although it is doubtful that a full fleet will have been delivered by then.