Guterres called the START extension a step towards reducing the risk of nuclear catastrophe

"The decisions of Russia and the United States to extend the START Treaty and start a dialogue on arms control were the first steps to reduce the risk of a nuclear catastrophe," TASS quoted Guterres as saying.

He also added that he was concerned about "the lack of progress in achieving the goal of a nuclear-free world."

Earlier it was reported that Guterres welcomed the plans of Russia and the United States to conduct a dialogue on mutual strategic stability.