A recording has emerged of radio exchanges between a Royal Navy frigate and Iranian armed forces vessels, moments before a UK-flagged oil tanker was seized in the Gulf on Friday.

Axar.az reports citing BBC.

In the recording, an Iranian vessel tells HMS Montrose it wants to inspect the Stena Impero for security reasons.

Chancellor Philip Hammond said the government would pursue "every possible diplomatic route" in response.

But Iran's ambassador to London warned the UK against escalating tensions.

Hamid Baeidinejad said in a tweet: "This is quite dangerous and unwise at a sensitive time in the region. Iran however is firm and ready for different scenarios."

The UK's foreign secretary has urged Iran to reverse the tanker's "illegal" seizure.

Jeremy Hunt said MPs would be updated on Monday about what "further measures" the government would take.