Media should avoid "bleak" reporting on the situation in sanctions-hit Iran and instead provide an image of "hope and joy," Tehran's chief prosecutor wrote Tuesday in an opinion piece published by Fars news agency.

"It is expected that the media take more responsibility and understand the circumstances of (the country's) situation, and refrain from painting a bleak picture and exaggerating the problems," Abbas Jafari Dolatabadi wrote.

"Instead, (the media) should create an atmosphere of hope and joy to prove that they can become a major asset in defending the Islamic Revolution."

Jafari Dolatabadi urged Iran's culture ministry to give "appropriate instructions" to the national media.

Many Iranian officials assert that draconian Western economic sanctions imposed over Iran's disputed nuclear programme are having little effect.

But the measures have cut the country's all-important oil production and exports, according to figures from OPEC and the International Energy Agency, and halved the value of Iran's currency this year.

Inflation has also accelerated, to 23.5 percent according to the central bank's latest annualised figure, and much higher according to expert observers.

Iran's culture ministry, which supervises the media, in July already warned the media against publishing reports on the impact of the sanctions so "the country is not hurt."

Supreme leader Ayatollah Ali Khamenei has called on Iran to establish an "economy of resistance" to counter the sanctions, notably by boosting domestic production and self-reliance.

He and President Mahmoud Ahmadinejad notably urged Iran to wean itself off its reliance on crude oil exports, with Khamenei calling them a "trap" inherited from before the country's 1979 Islamic Revolution.