A lawyer representing victims of phone hacking, including the family of Milly Dowler, is set to launch legal action in the United States against Rupert Murdoch's News Corporation, it has been reported.

Mark Lewis told the Associated Press he had teamed up with US-based lawyer Norman Siegel, who represented the families of many of those killed on September 11, 2001, to take on Murdoch.

It had previously been suggested by the Daily Mirror that some victims of the 9/11 attack had their phones hacked by News of The World.

The FBI opened an investigation into the accusations but so far no evidence has emerged to support the claim.

Lewis said that while the News of the World was a British newspaper, ultimate responsibility for the allegations lay with its US parent company, News Corporation.

He told Sky News that alleged corrupt practices, such as phone hacking and payments to police officers, by the tabloid would be against US as well as English law.

"Potentially this has very serious ramifications for News Corporation because the American damages in civil claims are far higher than might be awarded in a an English court," he said.

And he suggested that News Corp shareholders may now begin to seriously question whether it was wise for the Murdoch family to have such a tight grip on the company.

"I'm sure there are shareholders and other directors who will be looking at the family ownership and family control of a company," he said.

He predicted legal proceedings could begin in New York in the next few months.