TOKYO — The Japanese government announced Tuesday that it will spend $470 million on a subterranean ice wall and other steps in a desperate bid to stop leaks of radioactive water from the crippled Fukushima nuclear station after repeated failures by the plant's operator.

The decision is widely seen as an attempt to show that the nuclear accident won't be a safety concern just days before the International Olympic Committee chooses between Tokyo, Istanbul and Madrid as the host of the 2020 Olympics.

The Fukushima Daiichi plant has been leaking hundreds of tons of contaminated underground water into the sea since shortly after the 2011 earthquake and tsunami damaged the complex. Several leaks from tanks storing tainted water in recent weeks have heightened the sense of crisis that the plant's owner, Tokyo Electric Power, isn't able to contain the problem.

“Instead of leaving this up to TEPCO, the government will step forward and take charge,” said Prime Minister Shinzo Abe. “The world is watching if we can properly handle the contaminated water but also the entire decommissioning of the plant.”

The government plans to spend an estimated $470 million through the end of March 2015 on two projects — $320 million on the ice wall and $150 million on upgraded water treatment units that is supposed to remove all radioactive elements but water-soluble tritium.

The government, however, is not paying for urgently needed water tanks and other equipment that TEPCO is using to stop leaks.

The ice wall would freeze the ground to a depth of up to 100 feet through an electrical system of thin pipes carrying a coolant. That would block contaminated water from escaping the facility's immediate surroundings, as well as keep underground water from entering the reactor and turbine buildings, where much of the radioactive water has collected.

LONDON — A green Daimler owned and driven by Queen Elizabeth II has been sold at auction for $62,755.Auction house Historics said the queen used the vehicle from 2001 to 2004 to travel around Windsor Castle and to go to and from Buckingham Palace. It says the monarch at times drove the car herself.The auction house says the car comes with several modifications, including an adapted arm rest with a sliding space designed to hold the queen’s handbag. It added that the interior features lambs’ wool rugs and other extra fittings.The car was sold to an unnamed buyer in Surrey, near London, on Saturday.