Between which two countries was the Tashkent Agreement signed?

The Tashkent Agreement was signed in January 1966 between India and Pakistan to end the 1965 Indo-Pak war. It was mediated by the Soviet Union and signed by Indian Prime Minister Lal Bahadur Shastri and Pakistani President Ayub Khan in Tashkent (now in Uzbekistan). Tragically, Shastri died hours after signing the agreement. The agreement mandated withdrawal of troops to pre-war positions and restoration of diplomatic relations.