Havana residents watched from shore on July 27 as Russian warships arrived for the second time in as many months, in a visit that Cuba called routine. The patrol ship Neustrahimy, training vessel Smolny, and support vessels, all from the Baltic Fleet, are scheduled to depart on July 30. A Russian nuclear submarine, frigate, and support ships in June also flexed Moscow's muscles in the port of Havana, less than 160 kilometers from Florida. Russian naval activity -- though routine in the Atlantic -- has ratcheted up because of Washington's support for Ukraine, U.S. officials say. Relations between Cold War allies Russia and Cuba have markedly improved as the communist-run country battles an economic crisis it claims is due mainly to U.S. sanctions.