The USS Truxtun, a United States guided-missile destroyer, will carry out more exercises with allied ships in the Black Sea, its commander said on Saturday, amid an East-West crisis triggered by Russia's takeover of Crimea.
Commander Andrew Biehn was briefing reporters aboard the 300-crew destroyer as it bobbed gently in the spring sunshine in the Bulgarian port of Varna, a popular seaside resort.
The USS Truxtun last week took part in drills with Romanian and Bulgarian ships a few hundred miles from the Russian forces that entered Ukraine's ethnic Russian-majority territory of Crimea after protests toppled Ukraine's pro-Moscow president.
The US said the exercises were routine and had been planned long before the crisis erupted. But they coincided with air drills carried out by US and Polish fighter jets in Poland and NATO reconnaissance flights over eastern Europe.
The naval exercises carried echoes of the response during another standoff between the West and Moscow in 2008, when Russian troops poured into Georgia to support the breakaway regions of South Ossetia and Abkhazia. At that time, NATO sent ships to the Black Sea on what it called pre-planned exercises, sparking Russian accusations of a naval build up.
Last week's air and sea manoeuvres have sent a message of resolve to NATO members nervous about Russia's intentions in its former Cold War backyard.
"I cannot comment on our future operations but we'll take the opportunity to do some routine exercises with our allies in the region. Our operation was planned a long time before the start of the Crimean crisis," Biehn said.
Russian officials linked to Russia's gradual takeover of Crimea could face US and EU travel bans and asset freezes on Monday, a day after the Crimean province holds a secession referendum.
Moscow has shipped more troops and armour into Crimea and repeated its threat to invade other parts of Ukraine, despite Western demands to pull back.
Praying for peace
In Varna, residents gave a sense of the unease felt in parts of Europe about the West's response to the Ukraine crisis.
Bulgaria, an EU member since 2007, is caught between seeking closer integration with the bloc on the one hand, and nostalgia for its ties to the former Soviet Union and its heavy dependence on Russian gas supplies on the other.
"I'm not excited by the visit of this ship," said Georgi Kazakov, 59, a former teacher. "None of us want war... do the Americans know the Bulgarians and the Russians are like brothers?"
Despite its ships joining last week's exercises, Bulgarian leaders have said they will be among the worst hit if the Ukraine crisis gets worse.
"I just pray there'll be no war," said Ginka Borisova, a 64-year-old Varna pensioner. "I hope that politicians will be able to reach some compromise. It'll be the best way for Russia, Ukraine, Bulgaria, for all the people."
The Truxtun, named after an American naval hero and used last year in a Hollywood film, carried out a variety of different operations, including having a Romanian navy helicopter landing on it.
It carries missiles capable of shooting down planes, for attacking targets on land and shooting at submarines.