The detention in Iran of two British-Australian women and another foreign national believed to be Australian was reported by British media late on Tuesday.

The Australian government on Wednesday confirmed that three citizens had been detained in Iran.

"The Department of Foreign Affairs and Trade is providing consular assistance to the families of three Australians detained in Iran," a spokesperson for he government said as cited by AFP.

A blogger travelling through Asia with her Australian boyfriend and an academic from Cambridge University who was teaching at an Australian university were detained in separate cases, The Times reported.

The two women are believed to be currently held at the Even prison in Tehran, according to The Guardian.

They are said to be the first British passport-holders without Iranian nationality to have been imprisoned in Iran in recent years.

No further details are immediately available, with The Telegraph pointing out that the UK Foreign Office reportedly requested that the women's identities remain anonymous. At the same time the Foreign Office declined to comment on the incident, according to The Telegraph.

The Australian government is following both cases, The Telegraph reported.

Tulip Siddiq, a member of the UK Labour Party, commented on the alleged incident, accusing Iran of an escalation of "hostage diplomacy," according to The Times.

Neither Tehran nor London have officially commented on the reports.

In August, an Iranian court sentenced an Iranian-British dual national, Anushe Ashuri, to 12 years in prison on espionage charges, including charges of cooperation with Israel's Mossad intelligence agency.

The court also upheld a 10-year prison sentence against Aras Amiri, a British Council worker, who was arrested in 2018 and jailed for espionage.

Relations between the UK and Iran have deteriorated following the 'tanker war' in recent months.