Three Australian citizens were detained in Iran, the Australian government confirmed on Wednesday, adding that the Department of Foreign Affairs and Trade was providing the trio with consular assistance.

"Due to our privacy obligations, we will not comment further," the department said in a statement. It also urged Australians with upcoming trips Iran to "reconsider your need to travel."

UK media reported that one British-Australian backpacker and her Australian boyfriend had been detained while traveling through Asia 10 weeks ago. They are thought to have accidentally wandered onto a military base.

The third is an academic who lectured at the UK's Cambridge University and in Australia was recently sentenced to 10 years in prison. She is reportedly in solitary confinement, and the crime or crimes she was convicted of have not been made public.

"It does sound extremely concerning and of course the UK government will do everything we can to support any UK British citizens who are caught in Iran," British Secretary of State for Business Andrea Leadsom told Sky News.

The trio is being held in Tehran's Evin prison, where British-Iranian Nazanin Zaghari-Ratcliffe, 41, has been detained since 2016 on spying charges, according to media reports. 

Australia joins US-led mission

The incident is the latest in a series of Westerners who have been detained by Iranian authorities as tensions grow over tightened sanctions led by the United States. 

The news of the detention comes after Australia announced in August that it would join a US-led mission to protect shipping through the Strait of Hormuz. 

The Australian government advises potential visitors to the Islamic Republic to "reconsider" the need for travel, "due to the risk that foreigners, including Australians, could be arbitrarily detained or arrested."

wmr,es/sms (AP, dpa)