London: The Islamic State terror group has warned Britain of an attack more severe than the Paris assaults, saying the country will receive the "lion's share" of the slaughter for its "declaration of war against Muslims".
In the latest edition of its Arabic newspaper 'al-Naba' (The News), ISIS warns that the UK should be prepared for an attack more severe than in Paris last November which claimed 130 lives.
According to 'The Sunday Times', the article eulogises Mohammed Emwazi, the British murderer dubbed Jihadi John who was killed by a US drone strike.
It said "his words will never die" and that his message of slaughter did not end "with the blood of the soldiers of the caliphate who sent it to France in their own special way".
Britain will receive the "lion's share" of the slaughter "in response to its declaration of war against the Muslims", the group said in reference to last month's UK Parliament vote on airstrikes against ISIS in Syria.
An attack on Britain will be so severe, it claims, "that it will turn children's hair to white". The warning refers to a Quranic verse outlining the horrors of the Judgement Day.
ISIS had released a video last week that featured nine of the Paris attackers, including ringleader Abdelhamid Abaaoud.
By examining the montage frame by frame, 'The Sunday Times' has identified a string of potential targets, including Buckingham Palace and the National Gallery in central London.
A palace spokesperson said, "We never comment on security matters."
The National Gallery in Trafalgar Square is visited by more than 6 million people a year.
The fact that ISIS may have the gallery in its sights is reinforced by a new Europol report that says the terrorist group prefers "soft targets with a potential to cause mass casualties".
"We routinely monitor and review our security procedures," the gallery said.
Scotland Yard said, "We want the public to be alert, not alarmed. The current threat level across the UK from international terrorism remains at severe, meaning an attack is highly likely."
"UK police and security and intelligence services are working tirelessly to confront this terrorist threat and keep the public safe," it said.