Irving added that she'd tried to "grab the camera" but her cameraman had intervened.
"Jimmy said, 'No, no, he's got a gun!' So I let it go and they took off on the bike," she said.
However, Irving did manage to take a photo of the thieves as they cycled away.
The camera is reportedly valued at about A$25,000.
In an interview with Daily Mail, Irving explained that grabbing the camera was a "gut reaction."
"We weren't scared, we were just annoyed. I just grabbed the camera and Jimmy said 'He's got a gun,' so I said 'Show me the gun,' and it was that at that point I realised I was being silly and it was dangerous so I let go," she said.
Following the incident, Irving thanked fans on Twitter and praised her colleague for the way he handled it.
A spokeswoman for Channel 7 told news.com.au: "Seven News Europe correspondent Laurel Irving and cameraman Jimmy Cannon were the victims of an armed mugging in London.
"They had just finished a live cross for Sunrise ... when two balaclava-clad men on bikes approached and demanded they hand over the camera. The entire incident was recorded as pictures were still being fed back live to the Sunrise control room, and that vision has been handed over to local police. Both Laurel and Jimmy are safe and well."