The world's leading powers say a protective cover over the collapsed Chornobyl nuclear power plant would be completed by November 2017, despite insufficient funding.
German Environment Minister Jochen Flasbarth said a meeting of the Group of Seven (G7) major economies had secured "concrete pledges" for 530 million euros ($590 million) of the remaining 650 million euros needed to complete the reactor's "sarcophagus."
He added that he was confident that countries including Russia and China would provide the rest of the money following promises by both to do so.
The explosion and fire at the Chornobyl plant on April 26, 1986, was the world's worst nuclear accident.
A makeshift cover was built in six months after the explosion, but it was only expected to last a maximum of 30 years and has already had cracks repaired.
The new one, a convex structure, is being built over the original sarcophagus and the hope is it will allow the old reactor to be dismantled.