The Netherlands is to buy a further eight or nine F35 jet fighter planes, on top of the 37 already ordered, defence minister Ank Bijleveld has told Trouw in an interview.

The exact number of additional planes will be determined by the dollar euro exchange rate, Bijleveld said. At a total cost of €600m to €700m, the new buy will eat up half of the €1.5bn the government set aside for extra defence spending in its spring review.

The rest of the money will go on improving working conditions, special armed forces units and digital warfare, the minister said.

After years of wrangling, in 2014 the government agreed the Netherlands will buy 37 JSFs to replace the current fleet of ageing F-16s. The cost of the 37 planes was put then at €4.6bn, while operating costs will run at ‘a maximum’ €285m a year.