Instructions: Generate an explanation for the given claim using the provided supporting material from the paragraph. Please consider the following points while generating an output. 1) The claim will always have supporting proof in the paragraph, and the paragraph will have a clear point of view supporting the claim. 2) There can be instances where direct correlation to the claim is not available. Make use of the sentences in the paragraph to provide a corresponding output supporting the claim. 3) The explanation should be at least one and at most twelve sentences long.
Input: Paragraph: ClientEarth has taken action against the government twice before, in 2015 and 2016. The Supreme Court ordered the government to produce a new air quality plan in 2015. In 2016 the High Court ordered a new plan which came out earlier this year. However, ClientEarth says that the plan stills fall short of what is needed to bring pollution within legal limits as soon as possible and is therefore seeking a judicial review. "We need clarity from the government and for that we've been forced to go back to court," James Thornton, chief executive of ClientEarth, said in a statement. No one at the Department for Environment, Food and Rural Affairs was immediately available for comment. The firm said the reasons for the judicial review are that the latest government plan backtracks on previous commitments to make five cities in Britain introduce clean air zones by 2020. The plan also does not require any action from 45 local authorities in England, despite them having illegal levels of air pollution and it does not require any action from Wales. Under the EU's Air Quality Directive, member states were supposed to comply with nitrogen dioxide emission limits in 2010 - or by 2015 if they delivered plans to deal with high levels of the gas, which is produced mainly by diesel engines. Nitrogen oxide emissions reduce air quality and are associated with respiratory and other illnesses. Claim: Britain faces new legal challenge over air quality improvement plan.
Output:
New legal proceedings have been launched against the British government by environmental law firm ClientEarth over what it says is a failure to tackle air pollution, the firm said on Tuesday.