Carlyle Group is among private equity funds bidding for a stake in unlisted South Korean group Kyobo Life Insurance worth around $1.8 billion, sources with direct knowledge of the matter told Reuters.

Daewoo International and Korea Asset Management Corp (Kamco) are offering about a one third stake in the life insurance company in two separate sales, the sources said on Friday.

The sale offers a rare opportunity for private equity firms to invest in the life insurance sector, which is usually dominated by strategic investors who can pay higher valuations and command greater capital resources.

The stakes in Kyobo Life have come up for sale as Dutch group ING's Asian insurance businesses are on the block, a deal expected to fetch more than $6.5 billion.

Separately, private equity firm Vogo Fund is exiting its near 61 per cent stake in Tong Yang Life Insurance.

South Korean is among the more mature insurance markets in Asia, with premiums forecast to grow 3.8 percent this year and 3.9 percent in 2013, according to Swiss Re estimates. That compares with an Asian average of 4.4 percent for 2012 and 4.5 percent next year - steady growth that has been attracting private equity funds to the auction.-Reuters