Tehran AFP photo

Iran's Press Supervisory Board has suspended a hardline newspaper and cautioned two other outlets for criticizing last month's nuclear deal with world powers, Reuters reported Monday.

According to the news agency, the board suspended 9 Dey, a weekly newspaper that accused Tehran's negotiators of overstepping Supreme Leader Ayatollah Ali Khamenei's red lines in the negotiations, and referred its case to a court.

Censors also cautioned Kayhan, an influential conservative daily, and the Raja News website, in a setback for critics who assert that Iranian negotiators made too many concessions to reach the historic deal on July 14.

Conservative newspapers have been targeted in the past: in February 2014 the Supreme National Security Council sued a conservative journalist working for Vatan-e Emrooz (Today's Nation) for criticizing President Hassan Rouhani's foreign policy.

9 Dey was also censored several months ago after it was ruled that the paper had published articles insulting towards Islamic Republic founder Ayatollah Ruhollah Khomeini.

The move is still a rare one, however, as Iranian censors are more used to chasing publications perceived to be undermining the Islamic Republic's strict religious codes.

Most recently, censors in April banned monthly magazine Zanan-e Emrooz (Today's Women) for running an issue on "white marriage", a term used for unmarried couples living together in defiance of a law against extramarital sex.

The Committee to Protect Journalists (CPJ) listed Iran as the world's 7th most censored country in its 2015 annual report, noting the situation "has not improved under Rouhani despite the hopes of UN member states and human rights groups", according to Reuters.