Japan's Nikkei up but off 6-wk high, insurers gain

(Updates to midsession)

TOKYO, Feb 26 (Reuters) - Japanese shares gained on Tuesday after insurers such as Millea Holdings (8766.T: Quote, Profile, Research, Stock Buzz) rose on growing relief that U.S. bond insurers may have stabilised, with rising property shares helping boost the Nikkei to a six-week high.

But a lack of fresh buying factors and the downward drag of shares such as mobile carrier KDDI Corp (9433.T: Quote, Profile, Research, Stock Buzz), which tumbled after a ratings downgrade, kept gains capped after the Nikkei hit the psychologically important 14,000 level.

The benchmark Nikkei .N225 was up 0.5 percent at 13,983.51 by midsession, after earlier rising above 14,000 for the first time since Jan. 15. The broader TOPIX was also up 0.5 percent, at 1,362.49. (Reporting by Elaine Lies)