A spokesman for Emap's PR company Maitland confirmed the deal and told mad.co.uk it represents around £1 billion for shareholders.

In July, Apax was thought to have made a 1.3 billion offer with the view to merge it with Incisive Media, which the firm bought last year, before putting in a joint bid with GMG.

Apax is still understood to be planning to combine the two publishing groups together.

Carolyn McCall (pictured), chief executive of GMG, said: “We are delighted to have secured the board's recommendation for our joint offer with Apax Partners. Emap Communications is a strong business with a range of highly successful brands.

"The acquisition meets our requirements in terms of diversifying GMG's media interests, in line with our commitment to guarantee the long-term financial security of the Guardian. We look forward to working in partnership with Apax as we develop the business.”

Emap’s business-to-business titles include Retail Week, Broadcast, Nursing Times and Screen International.

The move has taken the market by surprise and is something Emap chairman Alun Cathcart ruled out after the sale of its radio and consumer business. “As part of the overall review, Emap assessed all options for Emap Communications [the B2B division], including a possible disposal," he said.

“However, the board believes the best value for shareholders will be achieved through continuing to operate this focused business on a standalone basis and, accordingly, the board has terminated all discussions with parties interested in Emap Communications.”

The proposed sale is set to end a 60-year-old company that started life as a regional newspaper group before building its consumer magazine empire from its first title Angling Times.

A spokesperson for Emap said the company would not comment on rumour and speculation and could not comment due to tight regulatory rules surrounding the deal.