The FBI issued a warning on Friday that Islamic State sympathisers are calling for attacks on churches and other holiday gathering sites in the United States.

The warning was issued after a publicly available list of US churches was posted on a social media site used by the jihadist group's supporters.

Earlier this week users of the Islamic State of Iraq and the Levant (Isil) supporting social media group published the list of churches which are located across all 50 states, CNN reported.

FBI and the Department of Homeland Security officials distributed a bulletin to police forces and private security firms across the country.

It came days after Isis claimed responsibility for the Christmas attack in Berlin in which a truck ploughed into a holiday market, killing 12 people and injuring 56.