A high-profile gathering of international donors gathered in Kiev last week and came up with $785 million or roughly €550 million for the construction of a steel shield for the ruined nuclear reactor at Chernobyl to prevent further radiation leaks in 100 years

The 20,000-tonne steel arch will be a more permanent outer shell that will replace the temporary casing now protecting the damaged reactor at Chernobyl.

The planned arch-shaped structure, which will take five years to build, will be 190 meters wide and more than 100 meters tall. It would be large enough to enclose St Paul's Cathedral in London, or the Statue of Liberty. It is designed so that the authorities could start dismantling the reactor from inside in 100 years.

This new steel shield will replace the concrete sarcophagus erected around the reactor in the months following the accident. This shield now has cracks, raising fears that 95% of the original nuclear material remaining inside the reactor could escape.

The pledged money will go to a project administered by the European Bank of Reconstruction and Development (EBRD), with part also funding a safe storage facility for spent nuclear fuel from inside the reactor.

Although short of the €740 million Ukraine was asking, the money pledged was enough to complete the construction of the shelter in time for both the new outer shell and the storage centre to be operational in 2015.

The EBRD said in a statement Tuesday that it would work with major donors "to close the remaining financial gap."

World governments had, so far, raised more than $1.6bn in international funding for Chernobyl safety works.

European commission president, José Manuel Barroso, said that "recent events in Fukushima" had persuaded them to respond to Ukraine's appeal which estimates that Chernobyl has cost the nation more than $12bn.

"More than ever, our responsibility is to join together our efforts to limit the consequences of such disasters and to prepare for the future," French prime minister, François Fillon, added,

Twenty-eight governments have so far offered to contribute. The European Commission was the biggest contributor with $143m at the Kiev Nuclear Safety Summit. The US pledged $123m and Britain, which still has more than 300 hill farms in Wales under radiation restrictions following the fallout from Chernobyl, will contribute $50m. The EBRD announced an extra $172m. Japan, Italy and Canada are considering whether to contribute.#30