The White House and Downing Street have signalled they intend to open up a new propaganda war by encouraging frontline soldiers to post positive video news stories about the Iraq occupation on internet websites.

LiveLeak, which specialises in hosting uncensored video footage filmed by military combatants, was cited by the prime minister, Tony Blair, on Friday in his keynote defence speech as an example of how terrorists had learned how to use the media to undermine public opinion.

LiveLeak, which gained notoriety at New Year for broadcasting footage of Saddam Hussein's execution, is one of several websites that host raw, uncensored footage of military engagements. LiveLeak emerged from ogrish.com, a website that showed uncensored news coverage of wars. The content often includes macabre and violent footage from war zones.

Blair said that gruesome images showing the "reality of war" were being used as a propaganda weapon by insurgents to influence public opinion that ultimately impacts on the morale of the armed forces.

His comments are being taken as a signal that British and US military are preparing to fight back via the internet. Blair's mention was the second time that LiveLeak had been namechecked in less than 24 hours by the leadership of the coalition forces in Iraq.

The previous day, White House press spokesman Tony Snow predicted that we are "likely to see in the weeks and months ahead" soldiers in the theatre using their cameras and sites such as LiveLeak or YouTube to share what they see.

Blair's mention of the site along with Snow's comments, made in a briefing to news bloggers ahead of President Bush's announcement of extra troop deployments in Iraq, are being widely interpreted as a sign that the Pentagon is preparing to exploit popular uncensored websites as part of its propaganda war.

"It wouldn't surprise me if governments already do it," said Hayden Hewitt, one of the founders of LiveLeak.com, the most popular of the military footage sites. "There is no quicker way of reaching millions and millions of people than through the internet and, as Tony Blair says, the old ways won't work any more," said Hewitt.

"He's acknowledged that the internet is going to change the way the military, the politicians and the public interact. You can't sweep things under the carpet any more."

Hewitt said that his company has welcomed the attention, but insists the impartiality of the website would not be undermined by pro-coalition videos being posted.

"It doesn't worry me, because viewers aren't so easily led; they don't accept things in the media at face value now. If governments start posting great material, then people will start watching it, but the floodgates are open now. They can try to ride the wave, but it's a bit late to try to manipulate people."

The unmoderated nature of websites such as YouTube and LiveLeak is a large part of what appeals to their viewers.

Dr Yaman Akdeniz, a law lecturer at the University of Leeds specialising in civil liberties on the internet, said the move was a recognition that the internet was becoming a key battleground for public opinion.

"Just two weeks on from the Saddam video, governments have started to get used to the idea that technology and the internet have a huge impact on society. We should not be surprised that people will attempt to use these powerful tools for their cause."

LiveLeak's Hayden Hewitt did not think that either side of the war would ultimately win a propaganda web war.

"When people talk about insurgent propaganda, I don't know many people who watch and aren't fully aware that it is propaganda," he said. "These guys do have the drop in the propaganda war, I suppose, but they only ever win over people who support them anyway."