The Islamic State’s threat to behead a British hostage if the UK and other Western governments continue to oppose it has once again brought into question the policy of not negotiating with terrorists.
The warning was made in a video showing the execution of American journalist Steven Sotloff released on Tuesday, when a third hostage reported to be the British man referred to was paraded in front of the camera.
Mr Sotloff was also shown alongside a similar warning to the US in footage of the beheading of James Foley two weeks before.
Authorities have confirmed that footage of Mr Sotloff's murder is genuine and British analysts have said the same jihadist in the video, who speaks with a English accent, killed both men.
David Cameron is chairing a Cobra meeting this morning to form the UK’s response but he is unlikely to deviate from the long-standing policy of refusing to pay ransoms on the principle it directly funds terrorism.
Isis is understood to have demanded millions of pounds for the release of many hostages, killing them after refusals to pay.
For Mr Foley, a US journalist held alongside Mr Sotloff after being abducted in Syria last year, the sum demanded was €100 million (about £80 million) as well as other conditions including the release of terrorists held by the US.
An email sent by Isis to his family a week before Mr Foley was killed claimed they were given “many chances to negotiate the release of your people via cash transactions as other governments have accepted”, although his relatives said they had only been contacted once before.
The G8 countries agreed not to pay ransoms to kidnappers at a summit in June last year but some governments appear to be giving into demands.
Earlier this year, four French journalists held by Isis in Syria were freed after, it was claimed, François Hollande’s government paid a hefty ransom.
Detailed reports were denied by the Élysée Palace, which pointed out that “President Hollande has said it is a very important principle that hostage-takers should not be tempted to take others”.
A month before that, two Spanish journalists were also freed by Isis, but the foreign ministry in Madrid refused to comment on whether money had changed hands.
There are several other cases, such as the case of four hostages from a French nuclear firm, where authorities have been accused of paying up and the Germans, Italians and Swiss have been implicated.
Ransom payments have become a highly lucrative source of revenue for terrorist groups, funding weapons, training camps, chemicals for explosives, travel tickets, renting and buying property.
The Foreign and Commonwealth Office (FCO) estimates that more than $60 million (£36 million) has been paid to militant groups over the last five years.
Last year a rise in the number of kidnappings had been recorded in Syria, Yemen, Nigeria and north-west Africa and it can be assumed a spike is currently being seen in Isis-controlled parts of Iraq.
The British Government’s policy of not making concessions dates back to the 1970s and aims to avoid encouraging more abductions and funding terrorism.
In pictures: Steven Sotloff
In pictures: Steven Sotloff
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Steven Sotloff inside Al-Fateh Mosque in Manama, Bahrain, in 2010
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Journalist Steven Sotloff, left, pictured in Libya in 2011
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Steven Sotloff pictured in 2010 near Lulu Roundabout in Manama, which later became the iconic center for the 2011 pro-reform protests in Bahrain
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Journalist Steven Sotloff pictured in Egypt
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Media gather outside Steven Sotloff's family home in Pinecrest, Florida
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Shirley Sotloff during a recent appeal to the captors of her son
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Pinecrest police officers are positioned at the home of Arthur B. Sotloff and Shirley Sotloff, the parents of American freelance journalist Steven Sotloff, in Pinecrest, Florida
A spokesman for the FCO said: “We have a long-held and clear policy of not paying ransoms or making any other substantive concessions to hostage takers.
“Successive British governments have followed this policy because we believe that the payment of ransoms enables terrorists to increase recruitment, strengthens their ability to organise and carry out terrorist attacks, and incentivises future incidents of kidnap.
“The resulting prolonged terrorist activity also severely hinders the development of countries where terrorists thrive, and prevents recovery from instability.”
The Prime Minister called Mr Sotloff’s murder “despicable and barbaric”.
He added: “My thoughts and prayers are with Mr Sotloff's family and friends as they deal with this appalling and tragic situation.
“As I have said consistently over the last few weeks, Isis terrorists speak for no religion.
“They threaten Syrians, Iraqis, Americans and British people alike and make no distinction between Muslims, Christians or any other faith.
“We have already been working hard to keep British people safe and we will continue to do all we can to protect our country and our people from these barbaric terrorists.”