The United States reportedly shelled out over half a billion dollars to a controversial British PR firm to run a top secret propaganda campaign in Iraq after the 2003 invasion by US-led coalition forces.

According to Bureau of Investigative Journalism and the Sunday Times, the Bell Pottinger firm was hired by the Pentagon to orchestrate and circulate pro-coalition material in the Iraqi media.

At the height of the Iraq war, the operation included “scripting soap operas, providing footage for local Arabic news networks and allegedly distributing insurgent videos used to track the individuals who watched them,” the Times reported on Sunday.

The $540 million campaign that ran from 2007 to 2011, is believed to be one of the most costly PR contracts in history.

Hundreds of the agency’s staff worked alongside high-ranking US military officials in their Baghdad Camp Victory headquarters.

In this Oct. 4, 2003 file photo, American soldiers aim towards a stone-throwing mob of ex-Iraqi soldiers near a former military airport in central Baghdad, Iraq. (AP Photo/Khalid Mohammed, File)

In this Oct. 4, 2003 file photo, American soldiers aim towards a stone-throwing mob of ex-Iraqi soldiers near a former military airport in central Baghdad, Iraq. (AP Photo/Khalid Mohammed, File)

Lord Tim Bell confirmed some parts of the story to the Times on Sunday, saying he was “very proud” of his firm’s participation in the covert military operation that was “covered by various secrecy documents.”

He said Bell Pottinger reported to the Pentagon, the CIA and the National Security Council on its media operations in Iraq.

But according to former Bell Pottinger employee Martin Wells, the firm’s work for the US military went far beyond the standard communications contract.

In a recent interview with the Bureau of Investigative Journalism, Wells described how after landing the job at Bell Pottinger, he was sent to Baghdad to conduct a “psychological operations” campaign.

Wells said he was given specific instructions to make short, 10-minute video clips that were to be shot in the style of al-Qaeda propaganda videos.

He said the video clips that were burned to CDs were embedded with coded linked to a Google analytics account that would reveal the IP addresses of whoever watched them to a top Bell Pottinger employee, and a top US military commander.

“If one is looked at in the middle of Baghdad…you know there’s a hit there,” he said. “If one, 48 hours or a week later shows up in another part of the world, then that’s the more interesting one, and that’s what they’re looking for more, because that gives you a trail.”

The Bell Pottinger firm has previously represented a number of controversial clients including the Sri Lankan government, ousted Thai Prime Minister Thaksin Shinawatra, and the wife of Syrian President Bashar Assad.