Reykjavík Summit continued, and U.S.–Soviet relations – already strained by the failure of the Geneva Summit the previous year – were further strained by the Daniloff–Zakharov espionage affair. At Reykjavík, Reagan sought to include discussion of human rights, emigration of Soviet Jews and dissidents, and the Soviet invasion of Afghanistan. Gorbachev sought to limit the talks solely to arms control. The Soviets acceded to the "double-zero" proposal for eliminating INF weapons from Europe, as initially proposed by President Reagan in November 1981 (INF denoting "Intermediate-Range Nuclear Forces" as distinct from ICBMs, or intercontinental ballistic missiles). The Soviets also proposed to eliminate 50%
Treaty on Conventional Armed Forces in Europe the establishment of an effective verification system. Meanwhile, in December the INF Treaty between the United States and the Soviet Union was signed, effectively allowing mutual inspections. During the May–June 1988 Moscow Summit, US President Ronald Reagan and General Secretary Gorbachev emphasized the importance of stability and security in Europe, specifically calling for data exchange, verification of these data, and then reductions. In December Gorbachev announced at the United Nations a unilateral withdrawal of 50,000 troops from Eastern Europe, and demobilization of 500,000 Soviet troops. In January 1989, NATO and the Warsaw Treaty members produced the Mandate for the Negotiation