Britain's navy will accompany UK-flagged ships through the Strait of Hormuz to provide protection after the US killing of Iranian military commander Qassem Soleimani inflamed tensions in the region, reports Reuters.
Britain's defence minister, Ben Wallace, ordered the HMS Montrose and HMS Defender to prepare to return to escort duties in the major oil shipping route as Prime Minister Boris Johnson came in for criticism for his silence over the killing.
Media reports have said Johnson is on holiday in the Caribbean.
"The government will take all necessary steps to protect our ships and citizens at this time," Wallace said in a statement.
Britain was forced to defend its ships through the world's most important shipping route last year after Iranian commandos seized a British-flagged tanker in the Strait. British forces had previously captured an Iranian oil tanker near Gibraltar that was accused of violating sanctions on Syria. The killing of Soleimani has raised fears that tankers could be targeted again.
Wallace said he had spoken to his US counterpart, Defense Secretary Mark Esper, and urged restraint on all sides.
"Under international law, the United States is entitled to defend itself against those posing an imminent threat to their citizens," he added.
Jeremy Corbyn, the outgoing leader of the opposition Labour Party, said he had written to the British prime minister to ask what was being done to protect UK nationals and others in the region.
"Boris Johnson should have immediately cut short his holiday to deal with an issue that could have grave consequences for the UK and the world," he said in a statement.
Iranian Supreme Leader Ali Khamenei, who gave Soleimani the country's highest honor last year, vowed "severe retaliation" in response to his killing. Thousands mourned his death in Iraq, Iran and Gaza.
The Pentagon accused Soleimani of plotting the embassy attack and planning to carry out additional attacks on US diplomats and service members in Iraq and the region.
Qassem Soleimani was the head of Iran's elite Quds Force and the mastermind of its regional security strategy. He was killed early Friday near the Baghdad international airport along with senior Iraqi militants in an airstrike ordered by President Donald Trump. The attack has caused regional tensions to soar and tested the US alliance with Iraq. Fearing escalation, NATO has suspended it's training activities in Iraq, while the British Navy has committed to escort every UK-flagged ship across the Straits of Hormuz.
Showing no signs of seeking to reduce tensions, the US president has since issued a stern threat to Iran on Twitter, saying that the US has targeted 52 Iranian sites that it would strike if Iran attacks Americans or US assets in response to the US drone strike that killed Soleimani. He later added that the US will use 'new' equipment to strike Iran.
The US strike on Soleimani's convoy at Baghdad airport also killed Iranian-backed Iraqi militia leader Abu Mahdi al-Muhandis, and it raised the specter of wider conflict in the Middle East.