A UK Government Cabinet Secretary has declined to say whether the UK would support Israel if reports it has launched missile strikes on Iran are confirmed.

The US has said that Israel launched missiles against Iran in a move which the White House did not endorse, some news outlets in the States are reporting.

Iran fired air defences at a major air base and a nuclear site near the central city of Isfahan after spotting drones early on Friday morning.

Furthermore, commercial flights began diverting their routes over western Iran without explanation as one semi-official news agency in the Islamic Republic claimed there had been “explosions” heard over the same city.

However, Iran has denied the reports in the American media, saying they are “not true”.

UK Cabinet Secretary Mel Stride declined to say whether the UK would support Israel’s reported action in Iran if confirmed.

Stride told Sky News: “I don’t want to get into hypotheticals, because of course, the question you’ve asked begs many other questions as to what form exactly that retaliation may or indeed may not have taken.”

The senior Tory also refused to say whether Israel would have UK backing for any further action.

“The overarching message on the military front is that de-escalation now is really important,” he said.

“We are very firmly engaged in counselling de-escalation and moderation at this particular moment.”

READ MORE: UK and US impose new sanctions on Iran in wake of attack on Israel

Speaking to Times Radio earlier, Stride said Israel did have a right to defend itself.

He said: “I think what we should say first and foremost, of course, is this is an evolving situation. These are unconfirmed reports as at the moment.

“But where we are as a Government is recognising very clearly that Israel has a right to defend itself. Indeed we joined in with others in doing exactly that when Iran made that a very significant attack on Israel at the weekend.

“At the same time though, we are pressing our Israeli allies and others in the region to really work hard towards de-escalation. So that is the important message that we have at the moment, but obviously, we need to wait to see how events unfold and exactly what has happened.”

Tensions have been high since Iran launched an assault on Israel amid its military action in the Gaza Strip and its own strikes targeting Iran in Syria.

READ MORE: David Pratt: Israel-Iran face-off has sinister echoes of 1991

US officials declined to comment early on Friday, but American broadcast networks quoting unnamed US officials said Israel carried out the attack. The New York Times quoted anonymous Israeli officials also claiming the assault.

Air defence batteries fired in several provinces over reports of drones being in the air, state television reported.

In particular, IRNA said air defences fired at a major air base in Isfahan, which long has been home to Iran’s fleet of American-made F-14 Tomcats – purchased before the 1979 Islamic Revolution.

The Israeli military did not immediately respond to a request for comment.

Iranian state television says nuclear facilities near Isfahan are “fully safe” after air defence batteries fired in the area.

The semi-official Fars and Tasnim news agencies reported the sound of blasts without giving a cause.

State television acknowledged a “loud noise” in the area.

Tasnim later published a video from one of its reporters, who said he was in the south-eastern Zerdenjan area of Isfahan, near its “nuclear energy mountain”.

READ MORE: Israeli drones 'luring people with sounds of babies crying before opening fire'

The footage showed two different anti-aircraft gun positions, and its details corresponded with known features of the site of Iran’s Uranium Conversion Facility at Isfahan.

“At 4.45, we heard gunshots. There was nothing going on,” he said.

“It was the air defence, these guys that you’re watching, and over there too.”

Dubai-based carriers Emirates and FlyDubai began diverting around western Iran at about 4:30am local time.

They did not explain, though local warnings to aviators suggested the airspace may have been closed.

Iran later announced it grounded commercial flights in Tehran and across areas of its western and central regions.

Loudspeakers informed customers of the incident at Imam Khomeini International Airport in Tehran, online videos purported to show.

Iranian state television began a scrolling, on-screen alert acknowledging a “loud noise” near Isfahan, without immediately elaborating.

Hossein Dalirian, a spokesperson for Iran’s civilian cyberspace programme, said on the X social media platform that several small “quadcopter” drones had been shot down.

It was not immediately clear where that happened or if it was part of the ongoing incident in Iran.

Around the time of the incident in Iran, Israeli warplanes flying over Syria’s southern province of Daraa struck a military radar for government forces after it spotted the fighter jets, according to the Britain-based Syrian Observatory for Human Rights, an opposition war monitor. It was not clear if there were casualties, the Observatory said.

That area of Syria is directly west of Isfahan, around 930 miles away, and east of Israel.

Meanwhile, in Iraq, where a number of Iranian-backed militias are based, residents of Baghdad reported hearing sounds of explosions, but the source of the noise was not immediately clear.

Separately, the US and Britain announced that they were imposing a new round of sanctions on Iran. The moves came as European Union leaders meeting in Brussels vowed to ramp up sanctions on Iran to target its drone and missile deliveries to proxies in Gaza, Yemen and Lebanon.

The US sanctions target individuals and entities that produce engines that power drones and are involved in steel production. The latest British measures target several Iranian military organizations, individuals and entities involved in Iran’s drone and ballistic missile industries.