The New START treaty, signed by the United States and Russia in 2010, was a nuclear arms reduction treaty which has now expired.
US President Donald Trump has now called for a brand new nuclear treaty, prompting fears of a new global arms race.
International Law Professor Al Gillespie told Andrew Dickens, "Mr. Trump is the one who let it void, he was saying, well, it's not fair that only America has these restraints in Russia.
"He wanted other countries like China to also have restraints, but China wasn't interested."
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