Sony Corp. is considering selling a 50 percent stake in its wholly owned insurance unit, Sony Life Insurance Co., to Dutch insurance group Aegon NV, sources close to their capital tieup talks said Friday.

The alliance will enable Sony to focus on its core businesses of electronics and games by scaling down its financial operations.

The timing and sale price are being negotiated, the sources said, adding the amount could reach 200 billion yen.

Under the planned tieup, Sony Life will become a 50-50 joint venture between Sony and Aegon, they said. The new venture is expected to continue using the Sony brand name.

Sony Life's insurance business comprises the central part of the Sony group's financial operations.

Sony Life rapidly grew on the strength of its huge sales force of more than 4,000, but managing the insurer has become a burden to Sony as a manufacturer, pushing it to form the alliance with the foreign company, they said.

With combined assets of more than 30 trillion yen, The Hague-based Aegon, which is late in entering the Japan market compared with other European insurers, will be ready to enter the Asian market, including promising China, by teaming up with Sony, they said.

With the alliance, Sony Life expects to obtain asset management knowhow from the Dutch group while offering diversified insurance products to its clients.

One of the reasons that Sony has decided to sell half of Sony Life's shares is that the insurer's assets grew to about 20 percent, or 1.7 trillion yen, of the group assets, making it difficult for the manufacturer to develop insurance products and manage the business as a nonspecialist, they said.

In the circumstances, Sony began negotiations on an alliance with several foreign financial institutions this spring and narrowed them down to Aegon in early August.