Livingstone wants 20 mph residential speed limit

(Reuters) - London mayor Ken Livingstone said on Monday he would try to impose a 20 mile (32 km)-per-hour speed limit on all London's residential streets to reduce the number of road deaths if he was re-elected for a third term in office.

Livingstone, who has adopted a tough policy towards road traffic, is neck-and-neck with Conservative rival Boris Johnson in polls in the runup to the May 1 mayoral election.

Last week luxury carmaker Porsche launched a legal challenge to a tax proposed by Livingstone to raise the eight-pound daily levy on all cars driving in the capital to 25 pounds for those with high fuel consumption.

That policy was designed to cut CO2 emissions. Livingstone said his latest initiative would dramatically cut road deaths in the city centre.

"I'll work with all London boroughs to designate all residential streets as 20 mph zones," he said in statement.

"Nine out of ten pedestrians will be killed if hit by a car travelling at 40 mph, but only one in forty will die if hit at 20 mph."

At stake for Johnson and Livingstone is one of the most powerful political prizes in the land.

As well as running an 11 billion-pound budget, the mayor will lead London up to its Olympic Games in 2012.

(Reporting by John Joseph; editing by Andrew Roche)