The Islamic State (Isis) has called for a new wave of terror attacks on mainland Europe that will "paralyse" the continent amid the political and financial turmoil of Brexit, a terror monitor has claimed. Daesh (Isis) regularly uses the encrypted messaging service Telegram to contact the outside world and the message was said to have been posted on there in the hours after the Brexit vote.

The message, according to terror threat monitor Site, reveals the expected negative economic impact of the United Kingdom leaving the European Union. But far more worryingly the extremists put out a threat calling on jihadists to attack Berlin and Brussels.

Only last week, Belgian police arrested a dozen people on suspicion of planning fresh attacks in the nervous country and neighbouring France, which is currently hosting Euro 2016. The arrests were made by counter-terrorism police in overdrive after the Brussels terror attack in March that left more than 30 dead.

In May, outgoing Prime Minister David Cameron suggested that IS warlord Abu Bakr al-Baghdadi would be "happy" if Britain voted to leave the EU in the 24 June referendum. Cameron added that he believed Russian PM Vladimir Putin would also approve of a Brexit.

He told a crowd: "It is worth asking the question: Who would be happy if we left? Putin might be happy, I suspect al-Baghdadi might be happy."

It follows reports in April from the German media that IS are sending terrorists to European beach resorts, where they plan to detonate suicide vests and use high-powered assault rifles to kill indiscriminately.

The Foreign Office (FCO) said in a statement: "There is considered to be a heightened threat of terrorist attack globally against UK interests and British nationals from groups or individuals motivated by the conflict in Iraq and Syria".

The Belgium federal police took 40 people for questioning following the raids last week which, they believe, may have been a cell planning to attack the Euro 2016 match between Ireland and Belgium.

On Wednesday 15 June, Belgian police received a tip-off about a group of IS fighters who left Syria and were headed for Europe with the intention of carrying out more attacks in Belgium and France,Reuters quoted security officials as saying.