Four Russian ships, including a nuclear-powered submarine, are scheduled to arrive in Havana next week, Cuban officials announced Thursday, emphasizing the “historically friendly relations” between the two countries amid heightened tensions over Western military support for Ukraine in its conflict with Russia.

In a press release, Cuba’s foreign ministry stated that the ships will be present in Havana from June 12 to June 17, specifying that none of them will be carrying nuclear weapons and assuring that their presence “poses no threat to the region.”

The announcement follows statements made by U.S. officials the previous day, indicating that Washington was monitoring Russian warships and aircraft expected to arrive in Cuba for military exercises. They suggested that the exercises were part of Russia’s broader response to U.S. support for Ukraine.

While expressing concern over the Russian military presence, the officials did not convey significant alarm. Nonetheless, the development aligns with Russia’s previous hints of potentially taking “asymmetrical steps” globally in response to President Joe Biden’s authorization for Ukraine to use U.S.-supplied weapons against targets within Russia’s borders, specifically to defend Kharkiv, Ukraine’s second-largest city.

According to Cuba’s Foreign Ministry, the four Russian vessels include the frigate “Gorshkov,” the nuclear-powered submarine “Kazan,” the fleet oil tanker “Pashin,” and the salvage tug “Nikolai Chiker.”

The foreign ministry also announced that one of the ships will fire a 21-gun salute upon the fleet’s arrival in Havana’s port, which will be reciprocated by an artillery battery from Cuba’s Revolutionary Armed Forces.