A US Coast Guard cutter was unable to get clearance for a scheduled port call in the Solomon Islands as concerns grow about China's influence on the Pacific nation.
The vessel, called the Oliver Henry, was conducting patrols as part of an international mission to prevent illegal fishing when it sought to make a stop to refuel on the island of Guadalcanal, according to the Stars and Stripes newspaper.
Coast Guard Lt Kristin Kam told the paper, which provides news to members of the US military, that there was no response from the Solomon Islands' government for diplomatic clearance for the vessel to stop.
The mission came to an end on Friday after the Oliver Henry was instead diverted to Port Moresby in Papua New Guinea.
The US Coast Guard is the maritime security, search and rescue and law enforcement service branch of the Armed Forces.
It said the cutter arrived in Papua New Guinea, roughly 1,800km (497 miles) from the Solomon Islands, on Tuesday "following a patrol in parts of the Coral Sea and the Solomon Islands".
The Royal Navy did not comment directly on reports that HMS Spey, also taking part in the mission, was also denied a port call in the Solomon Islands.
"Ships' programmes are under constant review, and it is routine practice for them to change," the Royal Navy said.
"For reasons of operational security we do not discuss details. The Royal Navy looks forward to visiting the Solomon Islands at a later date."
During the mission, called Operation Island Chief, the US, Australia, Britain and New Zealand provided support through aerial and surface surveillance for Pacific island nations participating in the operation, including the Solomon Islands.
The vessel was not allowed to stop in the country at a time when China has been assertively trying to expand its presence and influence in the Pacific.
Manasseh Sogavare, the prime minister of the Solomon Islands, raised concerns this year when he announced he had signed a new security pact with China.
The pact has raised fears of a Chinese naval base being established within 2,000km (1,200 miles) of Australia's northeast coast.
A Chinese military presence in the Solomon Islands would put it not only on the doorstep of Australia and New Zealand but also close to Guam, the US territory that hosts major military bases.
Both the Solomon Islands and China have denied their pact will lead to a Chinese military foothold in the South Pacific.
Mr Sogavare also raised eyebrows earlier in August when he skipped a memorial service marking the anniversary of the Battle of Guadalcanal, a key battle in the Second World War in which American and other allied forces wrested control of the islands back from Imperial Japan.
Wendy Sherman, US deputy secretary of state, whose father was wounded during the Guadalcanal campaign and who attended the memorial, said Mr Sogavare "missed an important opportunity" by failing to attend.
US Senator Marsha Blackburn met with Mr Sogavare in the Solomon Islands on Wednesday but it was not clear whether she raised the issue of the coast guard's refused port call.
The Tennessee Republican said in a statement on her website that her visit to the Solomon Islands as well as Fiji and Papua New Guinea "was an important step in showcasing America's commitment to the region and expanding our strategic relationships".
Lt Kam told Stars and Stripes that the US State Department had been in touch with the Solomon Islands government following the refusal of the port call and that they "expect all future clearances will be provided to US ships".
The development comes weeks after a visit to Taiwan by US House Speaker Nancy Pelosi sparked one of the biggest escalations in tensions between America and China for years.
Beijing believes Taiwan is rightfully part of its country - and President Xi Jinping hasn't ruled out military force to bring the island into China.
Meanwhile, US President Joe Biden has reinforced America's commitment to the island, even saying they would be willing to defend it militarily.