PORSCHE may take London mayor Ken Livingstone to a judicial review to challenge his plans to change the city's congestion charge to an emissions-based system from Oct 27. Mr Livingstone announced his plans last week to charge £25 (S$69) for cars which emit more than 225g of carbon dioxide per km. Meanwhile, those which emit less than 120g/km will enjoy a waiver of the £8-a-day fee.

A Porsche spokesman said: 'We will be looking at everything to make sure we check every area where it could be challenged. We think the proposals are disproportionate and unfair and will have a very limited effect on the environment.'

Porsche has only two models, the Boxster and Cayman, that fall below the 225g/km cut-off. Experts claim a judicial review could take place if it was possible to show that the mayor had not followed proper procedure or had exceeded his powers.

This article was first published in The Straits Times on Feb 23 2008.