Four Russian warships, including a nuclear-powered submarine, will arrive in Havana next week, Cuban officials said Thursday, citing “historically friendly relations” between both nations, and as tensions escalate over Western military support for Ukraine in its war with Russia.

Cuba’s foreign ministry said in a news release that the ships will be in Havana between June 12 and June 17, noting that none of them will carry any nuclear weapons and assuring their presence “does not represent a threat to the region.”

The announcement came a day after U.S. officials said that Washington had been tracking Russian warships and aircraft that were expected to arrive in the Caribbean for a military exercise. They said the exercise would be part of a broader Russian response to the U.S. support for Ukraine.

Those exercises will likely include Russian long-range bombers flying along the U.S. East Coast, according to CBS News national security correspondent David Martin. Russian warships have made port calls in Cuba before, and warplanes have flown along the East Coast in the past as well, but this will be the first time in five years both will happen at the same time, Martin said.

The U.S. officials said that the Russian military presence was notable but not concerning. However, it’s taking place as Russian President Vladimir Putin has suggested that Moscow could take “asymmetrical steps” elsewhere in the world in response to President Biden’s decision to allow Ukraine to use U.S.-provided weapons to strike inside Russia to protect Kharkiv, Ukraine’s second-largest city.

Martin noted the presence of four warships in Cuba “pales in comparison to the size of the exercises the U.S. military has been conducting with its NATO allies in Europe. So, this is not considered in any way a direct threat to the United States.”

Still, the U.S. military will be tracking the exercises “very closely,” Martin added. While the U.S. presence in the Caribbean is currently very light, the presence of military bases all along the East and Gulf Coasts means the U.S. could send ships and aircraft to the area quickly if necessary, Martin said.

Cuba’s Foreign Ministry said that the four Russian ships are the frigate “Gorshkov,” the nuclear-powered submarine “Kazan,” the fleet oil tanker “Pashin” and the salvage tug “Nikolai Chiker.”

During the fleet’s arrival at the port of Havana, 21 salvos will be fired from one of the ships as a salute to the nation, which will be reciprocated by an artillery battery of Cuba’s Revolutionary Armed Forces, the foreign ministry said.