Labour MP Tom Watson told the inquiry today that he had discovered that the News of the World put him under surveillance during the Labour Party conference in 2009.
The MP said the newspaper thought – wrongly – that he was having an affair. He said the surveillance "was a mission by Mazher Mahmood", the paper's former special investigations editor. Mahmood now works for the Sunday Times.
Watson, an outspoken critic of NoW publisher News International, also claimed that ministers in the last Labour government were constantly mindful of how their actions would be portrayed by Rupert Murdoch's newspapers.
The Labour deputy chairman told the Leveson Inquiry that during his time as a minister under Mr Brown there were frequent conversations about how something would "play out in The Sun".
The MP, one of Murdoch's fiercest critics over the phone-hacking scandal, became a junior minister at the Ministry of Defence in 2006, later moving to the Cabinet Office.
In his written evidence to the inquiry, he said: "I have no direct experience nor knowledge of the offer of favourable treatment in return for political support, yet I have never met a minister who didn't know the corporate aims of Rupert Murdoch."
Addressing the inquiry in person today, Watson said the News International newspapers were "the ones that had the connections and everyone was aware of it".
"As a minister when I discussed issues and policy there was always a conversation about how this would play out in The Sun," he said.
"There was a sense that there was a mystique about the News International stable, that they had unique access to Downing Street, and as a minister that was important, and the way you were portrayed in News International papers was important and they factored that into their thinking."
He called for reforms to ensure the public can have confidence in ministers' relations with newspaper executives.
"I have no hard evidence there was a craven understanding between politicians and senior executives at News International, but I do believe that is the general view of the public and we need reforms that ensure public confidence in those relationships is restored," he said.
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