The environmental licence granted to Dutch airport Schiphol was issued on “dodgy legal grounds”, the NRC reported on Tuesday.

The paper says documents from the agricultural ministry requested by green campaign group Mobilisation for the Environment (MOB) under freedom of information rules, show the minister relaxed the conditions for the airport so it did not have to cut the number of flights.

Schiphol had been operating without a permit for years, and the government had turned a blind eye to the situation.

The airport announced last year that it “satisfies the requirements of the Nature Conservation Act” following the purchase of nine farms whose carbon dioxide quotas were directly added to that of the airport.

But that is against European rules which state nature should be allowed to recover before pollution rights can be transfered to a new owner.

The documents also showed that civil servants were told by nature minister Christianne van der Wal to slow down work on the nature permit to allow Schiphol to continue to emit high levels of CO2.

“That will give them at least 18 months more,” the paper quotes a letter from the department to the minister, implying that the ministry expected environmental organisations to challenge the permit in court. MOB, Milieudefensie and Greenpeace are currently demanding the permit be cancelled.

The lenience shown to Schiphol was based on fears for jobs at the airport which would be affected if the number of flights were to go down, the documents show.

That is no excuse, environmental law expert Ralph Frins told the NRC. “You must abide by the law, especially if you’re the government,” he said.