The Dutch government was wrong to strip Dutch nationality from two convicted jihadis because the law making it possible was only introduced in 2017, the Council of State said on Wednesday.

The two men joined jihadi groups in Iraq and Syria in 2013 and 2014 and it is unclear if they were still active when the law was brought in, the highest Dutch administrative law body said. In addition, the organisations they joined were not on the official Dutch banned list prior to the implementation of the legislation.

The former junior justice minister Klaas Dijkhoff withdrew their Dutch nationality in 2017, after they were convicted of terrorist offences.

‘The withdrawal of Dutch nationality is a very severe move. That is why the law makes it clear it cannot be applied retroactively,’ the council said.

The two men’s current whereabouts is unknown.