A 300-foot Russian intelligence warship docked quietly in Havana harbor on Tuesday, a day before the start of historic U.S.-Cuba talks aimed at renewing diplomatic relations.

The Viktor Leonov CCB-175, "bristling with antennas and satellite dishes," fueled immediate speculation since Cuban authorities had failed to officially announce its visit to the Bay of Havana, which is known to often be used by cruise ships, Business Insider reported.

However, the Russian spy ship's presence was played down by U.S. officials in Washington, who claimed that it was perfectly legal and not at all out of the ordinary.

"It's not unprecedented. It's not unusual. It's not alarming," a defense official told Agence France-Presse.

"It may have a secret mission, but they're certainly not trying to hide the ship's presence," CNN's Patrick Oppman said. "It glided into Havana early this morning in full view of everyone to see" and docked where cruise ships usually do.

In late 2014, President Barack Obama announced plans to normalize relations with the still communist-governed island nation, which had previously been severed in the early 1960s after Fidel Castro's regime seized control of the island.

On Wednesday, Secretary of State for Western Hemisphere Affairs, Roberta Jacobson, is scheduled to meet with a Cuban counterpart headed by the United States director at the Cuban Foreign Ministry, Josefina Vidal, along with members of independent civil society, as well as religious and independent business leaders.

In a press release, Jacobson's office said the two-day visit's agenda will include "technical and logistical arrangements such as embassy operations, staffing and visa processing."

With the U.S. opening ties with Cuba again, the spy ship could be Russia's blatant demonstration that this relation won't weaken the island's relationship with Moscow, another government whose foreign and economic policies have often been at odds with those of the U.S. and its allies, Fox News reported.

Meanwhile over a year ago, the same ship, also called Meridian-class intelligence ship with a crew of around 200, reportedly docked in Havana on two separate occasions in February and March, with both unannounced visits lasting for a few days.