A pro-ISIS media group has threatened to attack Pope Francis as Christians around the world gear up to celebrate the birth of Christ.

Al-Abd Al-Faqir made the threat in a new propaganda poster showing a handgun being pointed at the Pope. It carries the slogan 'Don't think you are away from our attacks'.

Another poster threatened violence to 'slaves of the Cross' and showed a gunman creeping up behind the Pope, PJ Media reports.

Last year, the ISIS-affiliated media group Wafa Media Foundation made a similar threat of violence in the run-up to Christmas when it released a poster showing a man in a balaclava driving towards the Vatican. It was captioned 'Christmas blood ... so wait'.

According to PJ Media, ISIS produced an e-book in which it said any attack on the Vatican was likely to be met by strong resistence from the Mafia.

'There is no doubt that if Muslims want to take over Italy, the Islamic State European fighters will have to ally with other militias to fight the Mafia before the conquest of Rome,' it reportedly said.

The Vatican has previously acknowledged it could be the target of an ISIS attack. In 2015, Cardinal Pietro Parolin said the Vatican would ensure that the appropriate security measures were in place to deal with any threat.

'The Vatican could be a target because of its religious significance,' he said.

'We are capable of increasing the level of security in the Vatican and the surrounding area.

'But we will not let ourselves be paralysed by fear.'

ISIS has previously called for 'lone wolf' attacks to be carried out in Europe. In one ISIS-inspired attack in 2016, 12 people were killed at a Christmas market in Berlin.