Short answers, pulled from the story.
The Intermediate-Range Nuclear Forces Treaty was an arms control agreement between the United States and the Soviet Union, later inherited by the Russian Federation, banning ground-launched ballistic and cruise missiles with intermediate and shorter ranges. Ronald Reagan and Mikhail Gorbachev signed it on the 8th of December 1987.
The United States formally withdrew from the INF Treaty on the 2nd of August 2019, six months after suspending compliance on the 2nd of February 2019. Donald Trump had announced his intention to withdraw on the 20th of October 2018, citing Russian violations.
Trump cited Russian non-compliance, specifically the development and deployment of the SSC-8 cruise missile, known as the Novator 9M729, which the US said violated the treaty's range limits. His administration also pointed to China's growing arms buildup in the Pacific, since China was never a signatory to the treaty.
By May 1991, the United States and the Soviet Union had eliminated 2,692 missiles under the treaty, 846 by the US and 1,846 by the Soviet Union. Ten years of on-site verification inspections followed the destruction.
Paul Nitze led the American negotiating team, while Yuli Kvitsinsky headed the Soviet delegation during the early 1981-1983 talks. The treaty itself was signed by President Ronald Reagan and General Secretary Mikhail Gorbachev on the 8th of December 1987.
Russia announced on the 4th of August 2025 that it would no longer abide by the INF Treaty. This closed out a treaty that had already ceased to function for both major signatories following the US withdrawal in August 2019.