A new video has been posted on the internet purported to show Islamic State militants beheading American journalist Steven Sotloff.

The Associated Press and the SITE Intel Group, an organization that tracks the online activity of terrorist groups, both reported on Tuesday that the Islamic State has posted a video of the execution barely two weeks after the group formerly known as ISIS published a similar clip of American photojournalist James Foley suffering the same fate.

“I’m back, Obama, and I’m back because of your arrogant foreign policy towards the Islamic State,” a masked militant believed to be the same who executed Foley addresses the president in the latest video.

Kneeling in an orange jump suit, Sotloff is seen in the clip reading a statement to the president as Foley did before him.

“Obama, your foreign policy of intervention in Iraq was supposed to be for preservation of American lives and interests, so why is it that I am paying the price of your interference with my life?” Sotloff asks.

"As your missiles continue to strike our people, our knife will continue to strike necks of your people," the masked man says before killing Sotloff. Another captured civilian — David Cawthorne Haines of the UK — will be the next murdered unless "this evil alliance of America against the Islamic State" ends, militants warn in the video.

The White House could not immediately confirm the authenticity of the latest video, “A Second Message to America,” but press secretary Joshua Earnest said during a briefing on Tuesday that the administration’s “thoughts and prayers” are with Sotloff’s family. Jen Psaki, a spokesperson for the US Department of State, said she was “sickened” by the news, and British Prime Minister David Cameron called it an "absolutely disgusting, despicable act."

The alleged beheading also triggered a response from UN Secretary General Ban Ki-moon, who said on Wednesday that the world was “outraged” by the execution.

"We are all outraged at reports from Iraq about the brutal killing of civilians by ISIL (IS), including yesterday's reported brutal beheading of another journalist," he said during a trip to New Zealand.

He also described the beheading as “brutal,” insisting that "those perpetrators must be brought to justice.”

A 31-year-old freelance journalist who has written for Time magazine and the Christian Science Monitor, among others, Sotloff was kidnapped near Aleppo, Syria in August 2013. According to a profile published in the New York Times last month, Sotloff’s family tried desperately during the last year to keep his abduction quiet due to fears that the publicity would endanger him further, but changed course recently after the Islamic State warned that he’d be among the next executed lest the United State end its campaign against the militants.

Upon release of the Foley video last month, the Islamic State demanded that US President Barack Obama cease attacks on the group or else risk Sotloff becoming the next casualty of the group’s violent campaign in Iraq and Syria.

Sotloff’s fate, a militant warned Pres. Obama last month, “depends on your next decision.” In response, Sotloff’s mother posted a minute-and-a-half-long video plea asking Islamic State leader Abu Bakr al-Baghdadi to release her son.

“You, the caliph, can grant amnesty. I ask you please to release my child. I ask you to use your authority to spare his life,” Shirley Sotloff pleaded.

The US has since ramped up its attacks on the Islamic State, and international efforts are expected to be discussed by NATO member state’s during this week’s summit in Wales. During Tuesday’s State Dept. briefing, Psaki said that Pres. Obama has so far authorized at least 100 air strikes in Iraq against the Islamic State.