Trust, but verify

Trust, but verify (Russian: доверяй, но проверяй, romanized: doveryay, no proveryay, IPA: [dəvʲɪˈrʲæj no prəvʲɪˈrʲæj]) is a Russian proverb, which rhymes in Russian. The phrase became internationally known in English after Suzanne Massie, a scholar of Russian history, taught it to Ronald Reagan, then president of the United States, who used it on several occasions in the context of nuclear disarmament discussions with the Soviet Union.