 During December 2018, in response to President Trump's October announcement that he intended to withdraw the United States from the Intermediate-Range Nuclear Forces Treaty, Gillibrand was one of seven senators to cosponsor the Prevention of Arms Race Act of 2018, legislation prohibiting funding for a U.S. ground-launched or ballistic missile that had "a range of between 500 and 5,500 kilometers" until the administration provided a report meeting five specific conditions.Gillibrand also cosponsored this legislation when it was reintroduced by senator Jeff Merkley in the 116th United States Congress.In December 2018, after United States Secretary of State Mike Pompeo announced the Trump administration was suspending its obligations in the Intermediate-Range Nuclear Forces Treaty in 60 days in the event that Russia continued to violate the treaty, Gillibrand was one of six senators to organize a letter expressing concern over the administration "now abandoning generations of bipartisan U.S. leadership around the paired goals of reducing the global role and number of nuclear weapons and ensuring strategic stability with America's nuclear-armed adversaries" and calling on President Trump to continue arms negotiations.