Many of Asia's biggest economies are booming, driving world growth

Aviva, which also owns the UK's Norwich Union, plans to focus on its long-term savings business in the region.

The move is one of the the largest foreign purchases by a Japanese firm and makes Sumitomo the biggest non-life insurer in southeast Asia.

Many Japanese firms are looking to tap into the fast growing Asian markets as demand slows in their domestic market.

Sumitomo already has operations in 13 countries throughout the region.

Aviva's units are based in Hong Kong, Malaysia, Thailand, Singapore, the Philippines and Indonesia.