The Pentagon has denied claims Iranian forces thwarted an attempt by the US to detain a tanker carrying Iran’s oil in the Sea of Oman.
US officials said it was Iran's Revolutionary Guard (IGRC) who seized a Vietnamese-flagged oil tanker last month, while US naval forces were merely monitoring the situation.
"I've seen the Iranian claims, they are absolutely totally false and untrue ... it's a bogus claim," Pentagon spokesman John Kirby told reporters.
"The only seizing that was done was by Iran," Mr Kirby said.
Vietnam has been in talks with Iranian authorities over the seizure last month of a Vietnamese oil tanker off the Iranian coast, in an effort to guarantee the safety of the crew, the Southeast Asian nation said on Thursday.
Talks had taken place on a diplomatic level in Hanoi and Tehran "to verify information and settle the incident to ensure safety and humane treatment for Vietnamese citizens," Vietnam foreign ministry spokeswoman Pham Thu Hang told a regular briefing.
"The foreign ministry will continue to closely monitor the situation, and work with Iranian authorities to settle the case in accordance to the laws, and at the same time, will proceed with necessary measures to ensure the legitimate rights and interests of Vietnamese citizens," Ms Hang said.
Ms Hang said the captain of the Vietnamese tanker in a telephone call with the embassy on October 27 had confirmed all 26 crew had been treated well and were in good health.
Iranian state TV reported on Wednesday that the IRGC intercepted the US Navy's attempts to seize Iranian oil in the Sea of Oman. Without mentioning a date, the report claimed that the US Navy seized a vessel carrying Iranian oil and loaded its cargo on to another tanker.
The IRGC report said that before the newly loaded tanker was set to sail away, IRGC Navy troops descended on the ship and took control. They told state media, "the tanker carrying Iran's oil docked at the port of Bandar Abbas on October 25".
Iranian media identified the seized tanker as "SOTHYS" – the name tanker-tracking websites give for a Vietnam-flagged vessel – while state TV aired footage showing a red tanker surrounded by about 10 speedboats.
The report claims that the US Navy attempted to pursue the vessel with helicopters and warships but could not make it past the IRGC Navy. Further attempts to block the tanker and force it to change course failed and the vessel made it to Iranian waters.
These claims by the IRGC come nearly a month after it claimed that US speedboats had been intercepted in the Gulf. The IRGC is expected to release footage of the "piracy".
The IRGC has in the past tied these announcements highlighting Iranian strength to holy days, national holidays and memorials. The latest announcement comes on the eve of the anniversary of the US embassy takeover in 1979, and the national day of "fight against arrogance".
Iran has repeatedly warned the US about its military activities in the Gulf, saying the IGRC's naval forces have increased patrols to secure the passage of Iranian ships and combat fuel smuggling.
