A Royal Navy warship has arrived in the Persian Gulf ready to accompany British-flagged ships transiting the Strait of Hormuz in the latest escalation of regional tensions after Iran seized a British tanker this month.

Britain’s Ministry of Defense said Sunday the Type 45 destroyer HMS Duncan will join the frigate HMS Montrose to defend freedom of navigation.

Defence Secretary Ben Wallace said the Royal Navy will escort U.K. vessels until a diplomatic resolution is found to secure the route again.

The British-flagged Stena Impero oil tanker was seized in the Strait of Hormuz a week ago. Some senior Iranian officials have suggested the ship was seized in retaliation for the British navy’s role in seizing an Iranian supertanker off the coast of Gibraltar for violations of EU sanctions on oil sales to Syria.

The Strait of Hormuz links the Persian Gulf to the Gulf of Oman and is an increasingly contested chokepoint for oil tankers of different nations.

Earlier this week, it was confirmed the Royal Navy had been tasked with escorting British ships sailing through the Strait of Hormuz following the seizure of one ship by Iran.

Wallace confirmed safe navigation in the area is vital to world trade interests: He said:

Freedom of Navigation in the Strait of Hormuz is vital not just to the UK, but also our international partners and allies. Merchant ships must be free to travel lawfully and trade safely, anywhere in the world. I’m pleased that HMS Duncan will continue HMS Montrose’s fine work in helping to secure this essential route. While we continue to push for a diplomatic resolution that will make this possible again without military accompaniment, the Royal Navy will continue to provide a safeguard for UK vessels until this is the reality.

The UK is to send two more ships to the region later this year, according to Forces News. Type 23 frigate HMS Kent will take over from HMS Duncan, supported by RFA Wave Knight.

HMS Montrose, also a Type 23 frigate, will remain stationed in the Middle East until 2022.

The deployments are part of Operation Kipion – the name given to British forces in the Gulf and the Indian Ocean.

AP contributed to this story