Environmental organizations are calling the decision by a judge against a Dutch government plan to require Amsterdam’s Schiphol Airport to reduce the number of flights from 500,000 per year to 460,000 “a slap in the face” and a blow against cutting emissions and noise pollution.

The ruling came in a summary case brought by airlines and civil aviation organizations led by Dutch carrier KLM that sought to halt the planned cuts at one of Europe’s busiest aviation hubs.

The decision by a judge in Haarlem, a city close to Schiphol, came a day after the airport announced its own plans to phase out all flights between midnight and 5 a.m., ban private jets and the noisiest planes, and abandon a project for an additional runway.

The judge ruled that the Dutch government did not follow the correct procedure when it called on Schiphol to reduce flight numbers, a decision that was hailed last year as a breakthrough by environmental groups.

Wednesday’s decision means that Schiphol “may not reduce the maximum number of flights … to 460,000,” the court in Haarlem said in a statement.

In response, KLM said it plans measures that offer “a better alternative for achieving less noise and CO2 while meeting travellers’ need to fly.”

The airline said it would explain its approach in the next phase of the case. “This will investigate whether noise levels can be reduced around Schiphol using methods other than those envisaged by the ministry,” KLM said.

The government ministry responsible for aviation infrastructure said it was studying the ruling and considering its next steps.

The ministry said in a written reaction that it is “striving to find a new balance between the interests of residents and the living environment on the one hand and the economic importance of Schiphol for the Netherlands on the other.”

Environmental organizations issued a joint statement expressing their disappointment.

“Major polluter KLM is giving a slap in the face to local residents, the climate and the government that saved the company from bankruptcy,” groups including Greenpeace and Friends of the Earth said. “This ruling may cause a delay, but Schiphol will shrink. We are convinced of that. The government has now also started the correct procedures for this.”