A U.S. Navy guided-missile destroyer joined an Australian Navy frigate for exercises this week in the South China Sea, the U.S. Navy announced on Friday.

The USS Curtis Wilbur and the HMAS Ballarat spent a week of "cooperative operations with maneuvering drills and a replenishment at-sea with USNS Big Horn," a U.S. Navy statement said, in the contested area bordered by China, Taiwan, the Philippines and Vietnam.

The two ships conducted cross-deck helicopter operations, live-fire gunnery exercises and joint maritime operations.

The sea is the passageway for the majority of China's energy imports, and much of its total trade. Disputes in the area involve sovereignty of the islands, reefs, banks and other features of the South China Sea, with China's claims on the area leading to what observers have noticed is an increased military presence there.

"This exercise builds on the strong and enduring mateships that exist between the RAN [Royal Australian Navy] and U. S. Navy," commented Cmdr. Anthony Pisani, HMAS Ballarat commander, at the conclusion of the six-day exercise.

"It also shows that together we are committed to a secure and stable maritime environment, and promotes the importance of Navy-to-Navy relationships across the region," Pisani said.

The USS Curtis Wilbur is assigned to the U.S. Navy's 7th Fleet and conducts operations throughout the Indo-Pacific region.

The HMAS Ballarat arrived in the South China Sea after completing training with the Japan Maritime Self-Defense Force ship Murasame during the first week of June.

The two ships met near the coast of Japan for one day, conducting "various maritime maneuvers," the Australian Defense Department said.

US Navy warship enters Black Sea: Turkish media
Istanbul (AFP) June 11, 2021 –

A US Navy destroyer on Friday crossed the Bosphorus and entered the Black Sea, Turkey's Anadolu state news agency reported, as tensions simmer around Ukraine.

The crossing by the USS Laboon was reported as US President Joe Biden met Western leaders at the G7 summit in England.

He will then travel to Brussels for a meeting of NATO that is likely to focus heavily on the threat posed by Russia.

Biden will meet Russian President Vladimir Putin for high-stakes talks on Wednesday in Geneva.

"We are standing united to address Russia's challenges to European security, starting with its aggression in Ukraine," Biden wrote in The Washington Post before setting off on his first foreign trip.

Biden was Washington's pointman on Ukraine when he was vice president in Barack Obama's administration, supporting its drive to rid itself of Kremlin influence after a 2014 revolution toppled a Moscow-backed administration.

The US periodically sends warships to the Black Sea region in a show of support for Ukraine, often drawing protests from Russia.

Washington had notified Turkey that it may be sending two warships through the Bosphorus in mid-April, when Russia had built up its military presence in along Ukraine's border and in Crimea, which it annexed in 2014.

Those ships were never dispatched, as Russia pulled back its forces and the tensioned eased.