TOKYO, Feb 15 (Reuters) - Japan's Nikkei share average ended the session on Tuesday at its lowest level this month, weighed down by worries over aggressive U.S. rate hikes and as investors contemplated the implications of a potential Russian invasion of Ukraine.

The Nikkei slumped 0.79% to end at 26,865.19, its lowest close since Jan. 28 and below the psychologically significant 27,000 mark.

"As an index, it feels like we must be near the bottom," a market participant at a domestic securities firm said referring to the Nikkei.

"However, anticipation of rising U.S. interest rates makes it a difficult time to delve into the market."

Following disappointing earnings, construction machine maker Kubota tanked 12.62% to be the Nikkei's biggest percentage decliner, while staffing services company Recruit suffered a 12.46% plunge and was the biggest drag by index points by a wide margin.

Keeping traders on toes, the United States warned that Russia could soon invade Ukraine. The news on invasion pushed up energy prices, ramping up the risk of market volatility at the same time investors are fretting about the potential for the Federal Reserve to hike interest rates by half a percentage point next month.

Other notable decliners included chipmaking giant Tokyo Electron, which sank 2.40%, and startup investor SoftBank Group, which lost 2.09%.

Toyota Motor retreated 1.31% and Sony Group shed 2.28%.

Financials were the Nikkei's worst performing sector, dropping 2.44%, as a pullback in global long-term bond yields cut the profit outlook.

The broader Topix slid 0.83%. A decline of 0.96% in the value share index outpaced a 0.68% drop for growth shares.

At the other end, logistics company Nippon Express Holdings jumped 8.01% following a positive earnings report, making it the Nikkei's biggest percentage riser.

Advertising giant Dentsu rose 7.32% on favorable financial numbers.

Uniqlo store operator Fast Retailing was the biggest gainer by index points, registering a 1.04% advance.

(Reporting by Tokyo markets team; Editing by Sherry Jacob-Phillips)