Hundreds of Afghan protesters took to the streets on Friday, setting fire to an effigy of US President Barack Obama and demanding the death of a film-maker who they say insulted the Prophet Mohammed.

The demonstration in Nangarhar province, which borders Kabul to the west and Pakistan to the east, saw clerics in the Shinwari tribe call for a $100,000 bounty on the head of the producer of the film, "Innocence of Muslims".

An Obama effigy was also torched, said Zaher Ali, deputy chief of Ghanikhail district's council of clerics, but the protest passed off peacefully and fears about demonstrations in the capital Kabul were not realised.

"Death to America", and "death to the enemies of Islam", shouted the crowd, according to an AFP photographer, in what are fairly routine chants at anti-US protests in Afghanistan.

The low-budget movie, in which actors have strong US accents, portrays Muslims as immoral and gratuitously violent.

It pokes fun at the Prophet Mohammed and touches on themes of paedophilia and homosexuality, while showing him sleeping with women, talking about killing children and referring to a donkey as "the first Muslim animal".

Afghanistan is a devout Muslim country where anything seen as insulting to Islam is taken very seriously, often with a violent response.

Riots killed around 40 people earlier this year after US troops burnt copies of the Koran on a military base.

On Tuesday, US ambassador Chris Stevens and three other Americans were killed in Libya, reportedly by a mob angered by the film. Violent protests erupted across the Middle East on Friday.

The government has ordered an indefinite ban on YouTube to prevent access to the film, which it has condemned as "inhuman and insulting".

"This is the work of American Jews, their movie has hurt the sentiments of Muslims around the world," prominent cleric Enayatullah Baleegh told several thousand worshippers at the Pul-e-Khishti mosque in central Kabul.

Baleegh said it was not the first time Americans had insulted Islam and said the work by "two Americans" -- apparently referring to the film-makers -- had resulted in the deaths of the American diplomats in Libya.

"These two Jews and President Obama should be held accountable for the death of their diplomats because it shows the incompetency of the Obama administration and that he could not control such an insulting act," said the cleric.

Mystery remains over who is behind the film, amid conflicting claims of Jewish or Coptic Christian involvement.

Baleegh said the "filthy" producers should be held accountable for any US soldiers killed in Afghanistan as a result of Muslim anger over the film, but told worshippers that if they demonstrate "don't let it be violent".

The US embassy said staff had been ordered to "minimise outside activity" and reminded citizens that "past demonstrations in Afghanistan have escalated into violent attacks on Western targets of opportunity".

About 117,000 NATO troops are based in Afghanistan helping President Hamid Karzai's government put down a 10-year Taliban insurgency.