The weapons are an important part of America’s national security, the vice president has said US Vice President J.D. Vance has said the resumption of nuclear arms testing by Washington is required to ensure that the weapons remain in working order.On Thursday, US President Donald Trump announced that he had ordered the Pentagon to start nuclear weapons tests, citing strategic competition with Russia and China. “That process will begin immediately” in response to “other countries’ testing programs,” he said.Vance told journalists later in the day that “it is an important part of American national security to make sure that this nuclear arsenal we have actually functions properly, and that is part of a testing regime.” The vice president did not elaborate on what type of nuclear tests the US would be carrying out.Republican Senator Tom Cotton told Fox News that “we are not talking here about large-scale detonations with mushroom clouds in the desert or in the South Pacific. We are talking about very small, controlled, probably underground detonations.” Kremlin spokesman Dmitry Peskov reacted to Trump’s announcement by noting “the statement by [Russian President Vladimir] Putin, which has been repeated many times, that, of course, if someone abandons the moratorium [on nuclear testing], then Russia will act accordingly.”Responding to the US president's claims of other countries carrying out nuclear tests, Peskov said “we are so far not aware of this.” He clarified that last week’s launch of Russia’s new Burevestnik cruise missile, which has a small nuclear reactor that gives it a virtually unlimited range, was “not a nuclear test.”Chinese Foreign Ministry spokesman Guo Jiakun expressed hope that “the US will earnestly abide by its obligations under the Comprehensive Nuclear-Test-Ban Treaty and its commitment to a ‘moratorium on nuclear testing.’” Guo also urged Washington to “take concrete actions to uphold the international nuclear disarmament and non-proliferation regime, as well as global strategic balance and stability.” The US halted nuclear arms testing in 1992 under a Congress-mandated moratorium. Russia’s last test took place during the Soviet period in 1990, while China’s was in 1996.