what are two reasons the united states ended trade relations with cuba in 1961?

1) castro accused america of blowing up the ship sitting int here havanas harbor. 2.) castro said that the us and cuba needed to have the same amount of people in their pointed offices at the same time and the us in return brought alll of there people home and a week later withdrew from cuba saying that the only people from us going to be there wouild be the shipmen in guantanamo bay. ending relations with cuba

I could only find one reason, but the US ended trade with Cuba because Castro had ties with Russia during the Cold War.