Thirty-five years after the disaster at the Chernobyl nuclear power station on 26 April 1986, a new phase of remediation and decommissioning work is being planned that includes removing potentially unstable parts of the original sarcophagus, the European Bank for Reconstruction and Development said.

The sarcophagus was hastily constructed over the destroyed number four reactor in the weeks after the accident and contains the molten core of the 925-MW light-water graphite reactor and an estimated 200 tonnes of highly radioactive material.

However, the structure was never intended to be permanent and has deteriorated over the years and become less effective. A €1.5bn structure known as the New Safe Confinement (NSC) has been built to encase Unit 4 and the sarcophagus. 

The NSC will prevent the release of contaminated material and protect the sarcophagus from external impacts such as extreme weather.