Saudi Arabia has banned National Geographic over its cover story featuring the Pope for "cultural reasons".

The August edition of the Arabic version of the magazine was not allowed to be distributed in the country.

The editor of the magazine, Alsaad Omar al-Menhaly tweeted an explanation: "Dear readers in Saudi Arabia, we apologize that you did not receive August's magazine.

"According to the distribution company, the magazine was refused entry for cultural reasons."

The issue features the Pope and his "quiet revolution" to reform the Catholic Church.

The editor's note in the magazine celebrated the Pope's move to revitalise the Church and engage with culture, and says all world religions could follow his example. 

In Saudi Arabia, mosque and state are closely related. The Wahhabi religious authorities, who believe in Quranic literalism, would reject the notion that religion should be fluid or adaptable according to culture.

The editor suggested that religious institutions must be willing to adapt to the changing world, reported Foreign Policy.

It said religious pillars "are only tools aimed at preserving something, and if they are no longer capable of that, they must be altered."

Wahhabis seek to return to the practices of the first generation Muslims and are strongly opposed to the idea that religion should be reactionary toward culture.