The marriage of Sweden's Telia and Norway's Telenor is the latest in a series of link ups among telecoms firms. Mr Rosengren has been in talks with his Norwegian counterpart for more than two months to reach a final agreement. It was reportedly delayed because of disagreements over the location of several of the new group's divisions.
Analysts expect the merger to be approved by the Swedish and Norwegian parliaments.
The new group said it would expand its international presence and make acquisitions, possibly first on the mobile telecoms side. It would use its technological advances in mobile communications, satellite and Internet to expand internationally, especially in Europe, it said. Scandanavia currently leads the world in mobile phone usage. The group said it estimated that half the its sales would come from operations outside of Sweden and Norway within five years. The Norwegian firm's chief executive Tormod Hermansen will take over as chief executive of the merged group while the current Telia chief executive Jan-Ake Kark, will become the first deputy chief executive of the company.