Explanation

In June 1948, the Soviet Union, under the leadership of Joseph Stalin, blocked the Western Allies' access to Berlin.

It was deep within the Soviet-occupied zone of Germany.

In response, the Western Allies organized the Berlin Airlift to supply the city.

However, it was in 1961, under the leadership of Nikita Khrushchev, that the Soviet Union built the Berlin Wall to:

• Divide Berlin into two parts (East Berlin and West Berlin)
• Stop East German citizens from escaping to the West