Prime Minister Anthony Albanese has sought to allay fears about an increase in terror threats in Australia, following the US bombing of nuclear facilities in Iran at the weekend.

America’s Donald Trump administration confirmed it had completed an attack on three nuclear sites in Iran on Saturday, including Fordow, Natanz, and Isfahan.

Concern has been mounting the unilateral action could increase the terror threat in western cities, including Australia.

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Iran threatened the US with “sleeper cell” attacks if they were attacked, according to NBC.

The message was sent to Trump through an intermediary at the G7 in Canada last week, which forced the US president to leave the summit early to deal with the crisis in the Middle East.

On Monday, Albanese was asked about the terror threat, which is currently “probable”.

“Look, we are constantly monitoring (the threat),” Albanese said.

“The ASIO Director-General and our security intelligence agencies are constantly engaged in monitoring. There’s been no change in any of the advice that has been issued.”

Later in the press conference, Albanese touched on the possibility Aussies could become targets of attacks: “Obviously we’re opposed to any action against Australians or indeed against anyone else.”

Australian Foreign Minister Penny Wong said was reviewing advice for Australians travelling to the Middle East.

“There are always risks not only from escalation in the region but also potential for risk more broadly,” Wong said.

“I indicated publicly this morning that I have asked my department to consider whether there are any ... if there’s any alteration to travel advice more generally, which we will obviously make sure is updated.”

Albanese was asked a number of questions about the use of Australian military support in the region.

He refused to answer if Australia had intelligence in Iran “imminently” at the point of securing a nuclear weapon, prior to the attacks.

“Well, we don’t talk about intelligence matters, but we confirm, of course, that this was a unilateral action by the United States,” Albanese told reporters.

Albanese was questioned if his government was briefed by the US, prior to the attack on Iran.

Albanese confirmed it was “unilateral” action by the country.

He confirmed he has not spoken to President Donald Trump since the G7 summit.

Albanese wrapped-up the press conference by saying Iran still had a significant stake in diplomacy and peace, even after the bombing of its nuclear sites.

“Iran has an interest, an interest very clearly as well,” he said.

“I believe in in ensuring that there is not an escalation in the region.

“That is the incentive that they have. The United States have made clear their position, and we continue to call for dialogue.

“Had Iran complied with the very reasonable requests that were made, including by the IAEA, then circumstances would have been different.”