Russian Compliance with the Intermediate Range Nuclear Forces (INF) Treaty: Background and Issues for Congress [Updated February 8, 2019] [open pdf - 1MB]
"The United States and Soviet Union signed the Intermediate-Range Nuclear Forces (INF) Treaty in December 1987. Negotiations on this treaty were the result of a 'dual-track' decision taken by NATO in 1979 in response to concerns about the Soviet Union's deployment of new intermediate-range nuclear missiles. NATO agreed both to accept deployment of new U.S. intermediate-range ballistic and cruise missiles and to support U.S. efforts to negotiate with the Soviet Union to limit these missiles. In the INF Treaty, the United States and Soviet Union agreed that they would ban all land-based ballistic and cruise missiles with ranges between 500 and 5,500 kilometers. The ban would apply to missiles with nuclear or conventional warheads, but would not apply to sea-based or air-delivered missiles."
CRS Report for Congress, R43832
Congressional Research Service: https://crsreports.congress.gov/