During the Cuban Missile Crisis, who said "I am prepared to wait for my answer until hell freezes over."?

Adlai Ewing Stevenson II was an American politician and diplomat, noted for his intellectual demeanor, eloquent public speaking, and promotion of progressive causes in the Democratic Party. President Kennedy appointed Stevenson as the United States Ambassador to the United Nations. He served from 1961 to 1965. During the Cuban Missile Crisis in October 1962, Stevenson gave a presentation at an emergency session of the Security Council, where he forcefully asked Soviet UN representative Valerian Zorin if his country was installing nuclear missiles in Cuba. When Zorin appeared reluctant to reply, Stevenson punctuated with the demand "Don't wait for the translation, answer 'yes' or 'no'!" When Zorin replied that "I am not in an American court of law, and therefore do not answer a question put to me in the manner of a prosecuting counsel...you will have your answer in due course", Stevenson retorted, "I am prepared to wait for my answer until hell freezes over."