Foreign Secretary Jeremy Hunt was speaking while campaigning for the Tory leadership in Scotland (Library picture: PA).
Jeremy Hunt says Britain would consider joining the US in military action against Iran.
The Foreign Secretary's comments came as Foreign Office minister Andrew Murrison held talks with the Iranian government at the weekend where he said he was "clear" about the UK's concerns over Iran's activities.
Mr Hunt told the Daily Mail that Britain would "stand by the United States as our strongest ally" and "weigh up military intervention in Iran on a case-by-case basis".
"We do strongly believe that the solution is for Iran to stop its destabilising activity throughout the Middle East," Mr Hunt said.
"We are very concerned about the sabotaging of tankers that has happened recently, which is almost certainly Iran, and we're constantly in touch with the United States.
"We want to de-escalate the situation but we are of course extremely worried."
Mr Hunt, who is battling to become the next Prime Minister, said he has been speaking to his counterparts "regularly" about the Iran crisis which he called "extremely serious".
Last week, US President Donald Trump called off military strikes against Iran in response to the shooting downing of the US drone, after he was told 150 people would be killed.
However, American officials have since confirmed military cyber forces launched a cyber-attack against Iranian military computer systems on Thursday.
The attacks disabled Iranian computer systems that controlled its rocket and missile launchers, officials said.
Iran's foreign ministry spokesman Abbas Mousavi said the US "conducted a cyber-operation contrary to international law".
Ewan Lawson, a senior research fellow for military influence at RUSI, spoke to Forces News about the difficulty of the cyber-attack and why he thinks the US may have responded in this way.
"It is quite a challenging exercise," he said.
"The likelihood is these systems, these exercise systems, will have been separated from what we may think of as the internet so it wouldn’t be that easy to access it say from the continental USA.
"Instead, it is possible that someone may have had to either deliberately or inadvertently perhaps access the network through a pen drive or a floppy disk or a CD-ROM.
"Clearly the use sends a signal not just to Iran but to other nations that the US has this capability, albeit it runs the risk of now being blocked.
"One possible thought is that the US has other capabilities to achieve the same effects and considered that perhaps this one was vulnerable to being discovered anyway and therefore used it at this time because it was perceived as expendable."
He added that there had been no news yet on how successful the attack had been.
Meanwhile, US Secretary of State Mike Pompeo is visiting Saudia Arabia and then the United Arab Emirates amid the heightened tensions.
On Sunday, Mr Pompeo said he was seeking to build a "global coalition" against Iran, branding the country "the world's largest state sponsor of terror".