The nation’s competition watchdog has approved the sale of The Sunday Times and PerthNow to Seven West Media.

The decision will leave Seven West Media, which already owns The West Australian, with a substiantial share of Perth’s media market.

Australian Competition and Consumer Commission chairman Rod Sims said the commission had considered diversity and quality of news in reaching its decision.

“The ACCC reached the view that the proposed acquisition is, on balance, not likely to substantially lessen competition for either consumers or advertisers,” Mr Sims said.

“The large decline in print newspaper readership formed a major part of our analysis. We gave consideration to other online news alternatives including Fairfax’s WAtoday and the ABC’s West Australian website.”

WAtoday editor Simon White said it would be interesting to see how the deal was structured.

“My understanding is there won’t be any great change that would affect us at WAtoday,” he said.

“Everyone expects a narrowing of the market but only Seven West Media will know the scope of the situation.”

Seven West Media WA chief executive officer Chris Wharton said the acquisition of PerthNow and The Sunday Times was positive.

“Our integration of Channel Seven Perth, The West and our online businesses into the one media centre is delivering significant results,” Mr Wharton said.

The Sunday Times was founded in 1897 and has been owned by Rupert Murdoch’s News Corp and its previous incarnations since 1955.

PerthNow was launched in 2006 as the online partner of the The Sunday Times.

Media buyer John Byrne said he didn’t agree with the ACCC.

“The merger won’t receive much backlash because the average Joe won’t care and the majority of the media and the ACCC back the decision,” he said.

“However, I think the merger is likely to lessen competition.”