British Prime Minister David Cameron said the fallout from the conflicts in Syria and Iraq were the UK’s most serious security threat. Up to 400 UK nationals are believed to be fighting with Sunni militant groups.
“No-one should be in any doubt that what we see in Syria and now in Iraq in terms of Isis is the most serious threat to Britain’s security that there is today,” he said.
“The number of foreign fighters in that area, the number of foreign fighters including those from the UK who could try to return to the UK, this is a real threat to our country,” he said.
“That means stopping people from going, it means arresting people who are involved in plots, it means focusing our security, our policing, our intelligence effort on to that area of the world, on to those people.”
Cameron said he is committed to “rebuilding” diplomatic relations with Iran but will proceed with a “clear eye and hard head”.
The prime minister said the reopening of the British embassy in Tehran was an important step in that process.
Full diplomatic relations with Iran were suspended after attacks on the British embassy in Iran in 2011 but UK Foreign Secretary William Hague said the “circumstances were right” for the embassy to reopen following an improvement in bilateral relations in recent months.
The move comes as Iraqi forces are engaged in heavy clashes with Sunni Islamist militants across the country and amid reports that Iran is providing military assistance to its historic rival.
The election of a new Iranian president and a deal on Iran’s nuclear programme has led to renewed contacts between the UK and Iran this year.
Mr Cameron said he would have supported improved relations with Iran in any case but “what is happening in Iraq is not a reason for not taking that step”.
The UK has ruled out any role in future military intervention in Iraq and Mr Cameron said it was incumbent on the Iraqi government to “pursue an inclusive process that can unite the country”.
He also pledged to do everything he could to protect people from UK nationals fighting alongside Jihadi militants fighting in Iraq and Syria if they return to the UK.
Earlier on Tuesday, Mr Hague said the UK embassy would re-open “as soon as practical arrangements are made” as a sign of “increasing confidence” in the state of relations between the two countries.