I completely agree with my hon. Friend. A number of advisers and, indeed, serving Members on the Labour Benches now admit that their decision to promote diesel between 2000 and 2008 was not the right decision. The decision to promote diesel was a great shame, because we are now trying to deal with some of the consequences of that. It is important that we have cross-party co-operation to try to make sure that we tackle what is a very significant issue.