Newscom, which publishes the Southern Daily Echo and changed its name from Southern Newspapers last year, said it had been in talks with Portsmouth & Sunderland for the past few weeks and was interested in making a bid for the company. It has asked the Department of Trade and Industry to refer its possible bid to the Monopolies and Mergers Commission.
"We have had very friendly relations with them for some time and we're just next door," said Colin Rowley, Newscom's finance director. A combination between the two companies would make sense because there is a strong geographical fit between their operations.
Newscom joins its rival publishers Johnston Press and Newsquest in declaring an interest in Portsmouth. Charles Villiers, the former head of Scottish Radio's newspaper division, is also keen to mount a bid.
However, other groups which are talking to Portsmouth have yet to make their interest public. "We've had a lot of interest from the publishing and retailing side," a spokesman said.
Under UK media ownership rules, a change of ownership among newspaper publishers is automatically referred to the MMC. The watchdog is already investigating Johnston and Newsquest's offers, and is likely to consider a possible takeover by Newscom at the same time. "We just wanted to make sure that we were on the same timetable as the others," Mr Rowley said.