Air pollution hangs in the air lowering visibility in London, on April 2, 2014

Britain must take action in as "short as possible" a time to cut air pollution in line with European standards, the EU's top court ruled Wednesday.

The European Court of Justice said Britain's Supreme Court was entitled to order the British government to meet Brussels targets for .

Britain was meant to meet the targets by 2010 but has admitted that in some areas including the capital London it would not do so until 2025.

Climate campaigners filed a case with the British Supreme Court, which then asked the ECJ what action it was entitled to take under the EU's Air Quality Directive.

The European Court said British judges could take "any necessary measure, such as an order in the appropriate terms" to make the government comply with the EU targets.

It said the British government had to set up a plan as required by EU law to ensure that the time it exceeds the targets "is as short as possible."

The case is set to return to the British Supreme Court next year.

Campaigners hailed the result as a landmark for environmental protection in Britain and across Europe.

"This will force the government to finally take this issue seriously and come up with an urgent plan to rid our towns and cities of cancer-causing diesel fumes," said Alan Andrews, the lawyer for the British group ClientEarth, which brought the case.

"This sets a groundbreaking legal precedent in EU law and paves the way for a series of legal challenges across Europe. ClientEarth will spearhead these efforts to help people defend their right to clean air in court."