The Islamic State has issued a fresh terrorist threat to 'pigs of the cross' in Britain this Christmas.

One of its latest propaganda posters, spotted by the Site Intelligence Group, shows a terrorist pointing a gun at Santa in front of an antique shop on a British high street.

The poster warns: 'O pigs of the cross, the day is near when your carnage will be gifts for your children.'

Site Intelligence said the terrorist group had issued a 'plethora of threats to raise fear among Westerners and incite lone wolves' to attack Christmas and New Year celebrations. 

In another poster shared by Site Intelligence, ISIS says Christian holidays are 'a season for which the hungry lions eagerly await'.   The poster shows masked gunmen standing in front of burning buildings and a stretch of water turned blood red.

Last month, the pro-ISIS media group Al-Abd Al-Faqir published a poster showing a gun being aimed at Pope Francis with the slogan 'Don't think you are away from our attacks.'

European nations are on high alert after a gunman killed five at a Christmas market in Strasbourg, France, in an attack claimed by ISIS.  

The suspect, Cherif Chekatt, was shot dead by police two days later.  According to the BBC, he was on the 'fiche S' watchlist of people who posed a potential threat to national security. 

The Islamic State has repeatedly called for lone wolf attacks to be carried out on Europe and last year, warned of 'Christmas blood'. 

In Morocco, ISIS supporters are suspected of carrying out the murders of two Scandinavian tourists this week, although the Islamic State has not yet claimed responsibility. 

In 2016, 12 people were killed in a terrorist attack in Berlin in which a truck was deliberately driven into crowds of people at a Christmas market.

In the UK, where Christmas markets are a staple in many large towns and cities, security measures have been scaled up with crash barriers, armed police patrols, and bag searches becoming commonplace in recent years. 

The Vatican has said it will not be 'paralysed by fear' of an attack by ISIS. 

'The Vatican could be a target because of its religious significance,' Cardinal Pietro Parolin said in 2015. 

'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.'