Cuban Missile Crisis established a naval blockade on October 22 to prevent further missiles from reaching Cuba; Oval Office tapes during the crisis revealed that Kennedy had also put the blockade in place as an attempt to provoke Soviet-backed forces in Berlin as well. The US announced it would not permit offensive weapons to be delivered to Cuba and demanded that the weapons already in Cuba be dismantled and returned to the Soviet Union. After several days of tense negotiations, an agreement was reached between US President John F. Kennedy and Khrushchev. Publicly, the Soviets would dismantle their offensive weapons in Cuba and
Cuban Missile Crisis he had made to Kennedy might lead to a breakdown of the agreement between the Soviet Union and the US. To prevent that, Khrushchev decided to offer to give Cuba more than 100 tactical nuclear weapons that had been shipped to Cuba along with the long-range missiles but, crucially, had escaped the notice of US intelligence. Khrushchev determined that because the Americans had not listed the missiles on their list of demands, keeping them in Cuba would be in the Soviet Union's interests. Anastas Mikoyan was tasked with the negotiations with Castro over the missile transfer deal that was designed