US authorities have seized dozens of websites linked to Iranian groups, including the Revolutionary Guards, accusing them of spreading misinformation and operating in the country without licences.

In a statement on Tuesday evening, the US Department of Justice said 36 websites had been taken down, 33 of which were operated by the Iranian Islamic Radio and Television Union.

A further three of the seized websites were operated by Kata’ib Hizballah, which the state department has designated a terrorist organisation.

In October, the US Treasury department imposed sanctions against the IRTVU for being “owned or controlled” by the Islamic Revolutionary Guard Corps, and for its role in targeting the 2020 presidential election with what officials described as “brazen attempts to sow discord among the voting populace by spreading disinformation online”.

All of the websites seized were owned by US companies, but both IRVTU and KH were required to get licences from the US government before operating in the country, which they had not, the justice department said.

The website suspensions came days after the landslide electoral victory of conservative cleric and judiciary chief Ebrahim Raisi in Tehran, which gave regime hardliners control over all branches of the Iranian state for the first time in almost a decade.

The Biden administration is seeking to re-enter the 2015 nuclear pact with Iran and has embarked on several rounds of indirect negotiations in Vienna, although those efforts have yet to deliver a breakthrough.

Tehran has repeatedly demanded Washington lift sanctions before it agrees to curb its nuclear programme. Since the Trump administration withdrew from the deal, Iran has violated limits on its nuclear production, causing concerns at the UN’s nuclear watchdog.

President Joe Biden has promised to rejoin the nuclear agreement if Tehran returns to full compliance with the deal. But his administration is under pressure from US politicians, Israel and Washington’s Arab partners to take a tough line on Iran’s support for regional militias and its missile programme.