IRANIAN President Hassan Rouhani has been photographed hiking in the mountains outside Tehran, his black turban replaced by a baseball cap.

The photos, which appeared on his personal website on Friday, came as the recently elected leader has sought to present a friendlier and more moderate image of the Islamic republic, which reached a landmark nuclear deal with the West last month.

The pictures show Rouhani, usually seen in the turban and robes favoured by Iran's clerics, in a black baseball cap and matching ski jacket walking along a dirt road and using hiking poles.

He is seen mingling and chatting with other hikers, including a group of women, and posing for a picture with the sun setting over Tehran in the background.

The website said Rouhani - who defeated a pool of conservatives in a June presidential election after vowing to engage with the West - goes hiking once or twice a week.

Iran's supreme leader Ayatollah Ali Khamenei, who must approve all major decisions and who is seen as more distrustful of the West, is also fond of hiking, and state media have published similar pictures of him in the past.

Iran and a group of major powers broke through a decade of gridlock last month to agree on an interim deal that would freeze parts of Iran's controversial nuclear programme while easing some of the crippling international sanctions against it.

The West and Israel have long suspected Iran of pursuing a nuclear weapons capability alongside its civilian program, a charge denied by Tehran.