British Prime Minister David Cameron on Tuesday condemned as "despicable and barbaric" a new video that was released by the Islamic State and which shows the brutal beheading of Jewish-American journalist Steve Sotloff.

According to the Mirror, Cameron said he would be chairing a meeting of the Government's Cobra emergency committee on Wednesday morning.

"If verified, this is a despicable and barbaric murder. My thoughts and prayers are with Mr. Sotloff's family and friends tonight as they deal with this appalling and tragic situation,” said the British leader.

"As I have said consistently over the last few weeks, (IS) 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,” he added.

"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. Tomorrow morning I will chair a Cobra meeting to review these latest developments," said Cameron.

Tuesday’s video emerged just weeks after uploading a similar video of murdered journalist James Foley

In the video, entitled "A Second Message to America," Sotloff appears in a similar jumpsuit to Foley's before he is beheaded by an Islamic State terrorist. IS had threatened to kill the freelancer unless the U.S. ceased its airstrikes on the terror group in Iraq. 

The terrorists have now threatened abducted civilian David Cawthorne Haines of the UK with death as well, ending the video with threats to his life until "this evil alliance of America against the Islamic State" ends immediately. Haines, like Foley and Sotloff, is clad in an orange prison jumpsuit. 

Several intelligence experts told the New York Times that the man has the same accent and characteristic as the "John of London" reportedly responsible for the Foley murder.

The experts also proposed that Foley and Sotloff had actually been executed on the same day - along with Haines as well - and that IS is stringing the U.S. and others along to "space out" the videos for maximum effect and leverage. 

Cameron recently urged for action against IS recruitment in the Middle East and in Britain.

"If we do not act to stem the onslaught of this exceptionally dangerous terrorist movement, it will only grow stronger until it can target us on the streets of Britain," he said. "I agree that we should avoid sending armies to fight or occupy, but we need to recognize that the brighter future we long for requires a long-term plan."

On Friday, Britain raised its terrorism alert to the second-highest level over the IS threat. The government in London said there was no evidence an attack was imminent but the assessment of the latest intelligence by security chiefs justified elevating the international threat level to "severe", meaning a strike was "highly likely".