The pressures of leading a country engulfed in a complex and chaotic civil war may be taking its toll on the health of Syria's embattled leader.

Amir Taheri, a columnist with the Saudi-owned London based newspaper Asharq Al-Awsat, claimed in a piece published in Saturday’s edition that Bashar al-Assad's mental health is suffering after almost six years of conflict.

Citing officials from Syria's ally Russia, he said Moscow insiders claimed on background the president is “exhausted” due to “psychological pressures.”

“This is why Russian officials, speaking in private, now drop hints that Assad is ‘exhausted by five years of war and tension’ and may be is even developing a nervous tick in his left eye as a result of “psychological pressures,” Mr Taheri wrote.

The comment was picked up by various anti-Syrian regime outlets online, where the headline morphed into claims that Mr Assad - who trained as an doctor - has been hospitalised with a nervous condition.

During an interview with The Sunday Times late last year, Mr Assad said he did not lose sleep at night over his role in the civil war, which the UN says has claimed 400,000 lives and driven half of Syria’s population from their homes.

Asked if the deaths of children killed in Aleppo and elsewhere weigh on his mind, he laughed and said, “I know the meaning of that question.”