The ruling came at the end of a judgment which saw the government defeated for the third time by ClientEarth over air pollution.
It means, for the first time ever, that ClientEarth can immediately bring the government back to court if it prepares a plan which is unlawful.
This move, which means the environmental lawyers will not need to apply for permission to bring judicial review, was described by the judge as “wholly exceptional”.
ClientEarth lawyer Anna Heslop said: “The Judge has effectively allowed us to bring this matter straight back to court without delay if the government continues to fall short of its duties.
“We are extremely grateful for this because it means we will be able to monitor the government’s actions even more effectively and hold them to account.”
Handing down judgment, Mr Justice Garnham said: “The history of this litigation shows that good faith, hard work and sincere promises are not enough… and it seems court must keep the pressure on to ensure compliance is actually achieved.”
He added that this is the third unsuccessful attempt by the government to produce a plan to bring down air pollution to legal levels as quickly as possible and all the while people in towns and cities are at “real risk” from air pollution.
Mr Justice Garnham praised ClientEarth as a “valuable monitor of the government’s efforts”.
Immediately after the judgment the Prime Minister and Defra wrongly claimed the judge had “dismissed two of the three complaints” brought by ClientEarth. In fact, the judge ruled in ClientEarth’s favour on two of the three grounds.