Sources close to PA said that other major shareholders such as Trinity Mirror, News Corporation and Daily Mail & General Trust, are thought unlikely to sell.
Rob Merrick has been appointed lobby editor of the new Westminster service, called Central Press Lobby. He insisted that news from his team will continue to be ringfenced from PA's general news wires.
Merrick and four lobby correspondents are to provide dedicated parliamentary coverage for regional newspapers, TV stations, magazines and websites.
He said: 'We are aimed at organisations who don't want to staff Westminster themselves. They have a share of a journalist, who provides news on particular areas of interest or a patch. The style of what we do will be the same, but by merging with the PA team we will be able to cover more.'