Nick Robinson loses his cool and declares his true colours

Nick Robinson was caught on camera grabbing and smashing a protester's placard after filming a report (YouTube )

The crowds passing through Westminster on Wednesday evening would not have been too surprised to encounter one of the political village's most famous faces, with its trademark thick black spectacles and the lights of the camera crew bouncing off his shiny dome.

What might have caused alarm, however, was that the BBC's political editor Nick Robinson was in the process of violently stamping on a placard he has just wrested from the hands of anti-war activist. When challenged over this most partial of activities, which was unfortunately captured on camera and uploaded to the internet yesterday, Mr Robinson said he was "not even remotely ashamed".

Those who watched the BBC's Six O'Clock News may have witnessed the irritation which caused the usually mild mannered correspondent to engage in this moment of rage: the placard wielder had been continually interrupting his broadcast. In the footage Mr Robinson is shown trying to pull apart the sign – which read "Cut the war not the poor" – before stamping on it, while a protester shouts: "You should be ashamed of yourself, mate."

Confronted after the incident by the camera-wielding activist, Mr Robinson remarked: "I'm not remotely ashamed of myself." But a posting on his blog yesterday evening revealed he has since softened his stance.

"I have a confession," he wrote. "I grabbed the sign and ripped it up – apparently you can watch video of my sign rage in full glorious technicolour on the web. I lost my temper and I regret that."