A lawyer for News International has said Labour MP Tom Watson should not be allowed to question them.
Tom Crone is being quizzed by the culture committee about phone tapping at the News of the World.
He threatened to complain to the Parliamentary authorities if Mr Watson takes part in the questioning.
Mr Watson, who is involved in a legal case with News International, accused the firm of "attempting to interfere with the work of the committee".
One-Minute World News 
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