"A new era is coming? I think that the answer to this question has to be given as soon as possible. The best response would be to agree to launch consultations or talks involving Russia and the United States on the fate of the New Start after February 5, 2021. There is not much time left, less than four years. This is the term of the already turbulent Trump presidency," he wrote on Facebook.
President Trump also pledged to build up America's nuclear arsenal, adding that the United States is "never going to fall behind on nuclear power."
Trump did not specify whether he wants to renegotiate the deal, but his remarks on strategic weapons have caused concern in Russia, with Kosachev pointing to what he referred to as bad news in this regard.
"The current treaty will expire in 2021 and will not be automatically extended. If the parties do not agree on the next steps, then it would simply cease to have an effect and nuclear weapons would not be limited by any legal documents," he warned.
Critics say that agreements like the New START, which entered into force in 2011, and the Intermediate-Range Nuclear Forces (INF) Treaty have been instrumental in providing global security and preventing a strategic arms race.
Alexey Arbatov of the Moscow-based Institute of World Economy and International Relations linked the fate of the New Start to the future of the INF Treaty, another point of contention between Russia and the United States in recent years.
"If the INF Treaty falls, then the New Start will also collapse," he told Gazeta.ru. "They will be followed by the entire system of non-proliferation of nuclear weapons."
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