Flags fly in front of the tents of Camp Justice in Guantanamo Bay Naval Base, Cuba, on April 18, 2019. (AP)

The Cuban Ministry of Foreign Affairs announced its categorical rejection of the entry of a US nuclear-powered submarine into the US naval base in Guantanamo Bay.

This action is a "provocative escalation of the United States, whose political or strategic motives are not known," the Ministry said in a statement.

An official statement by the Cuban Foreign Ministry indicated that this spot, for many years, "had no strategic or military importance for the United States, and its continued occupation is only for the political aim of trying to violate Cuba's sovereign rights."

"The usefulness of this spot has been reduced in recent decades; it became a center of detention, torture, and systematic violation of the human rights for dozens of citizens from different countries," the statement added.

The statement stated that the United States has established more than 70 military bases in the region, adding that they "constitute a threat to the sovereignty and interests of the peoples of Latin America and the Caribbean."

The Cuban Foreign Ministry called for an end to the provocative actions, stressing that "33 countries in the region adopted the declaration of Latin America and the Caribbean as a Zone of Peace, on January 2014, in Havana."

Read: How the US is still punishing Cuba 6 decades on

Cuba confirmed its rejection of the US military presence in Cuba, calling for the return of illegally occupied territories in Guantanamo Bay and warning against the danger of the presence of nuclear submarines with the US armed forces in the neighboring Caribbean region.

It is worth noting that the US military base in Guantanamo extends over an area of 117 square kilometers and has been occupied by the United States for 121 years against the will of the Cuban people.

Havana describes it as the colonial remnants of the illegal military occupation of Cuba, which began in 1898.