TOKYO, Feb 18 (Reuters) - Japanese government bond (JGB)

yields rose to their highest levels in more than a decade on

Tuesday as an auction for 20-year bonds saw low demand as

investors continued to puzzle out how fast and high the Bank of

Japan (BOJ) may increase interest rates.

The 10-year JGB yield ticked up 2.5 basis

points (bps) to its highest since November 2009 to 1.41%, while

10-year JGB futures fell 0.37 points to 139.01 yen.

The 20-year JGB yield climbed 6 bps to

2.065%, a level last seen in April 2011, following the auction

of corresponding bonds. It was last at 2.06%.

The bid-to-cover ratio, a common measure at auctions where a

large number indicates more demand, came in at just 3.06

compared with 3.79 in January. It was the weakest showing of

demand since October.

Analysts cited uncertainties about the outlook for the BOJ's

rate hike path among reasons for the poor result.

"While the yield level looked fairly positive for the

auction, we're in a situation where we don't know where yields

will stop. That factor worked as a negative," said Yurie Suzuki,

a market analyst at Mizuho Securities.

Yields move inversely to bond prices, rising as bonds are

sold and prices fall.

Market players have been expecting the BOJ to continue

gradually hiking rates as it normalises monetary policy, but

questions remain about the pace and extent.

That's creating a strong sense of uncertainty, putting

upward pressure on bonds, said Suzuki.

Recent hawkish comments from policymakers and sticky

inflation are pushing forward rate hike expectations, shaking

long-held views that rates would not rise much.

Remarks by BOJ board member Hajime Takata on Wednesday and a

domestic CPI report on Friday will be in focus.

The two-year JGB yield and five-year yield

both ticked up 1.5 bps to 0.82% and 1.065%,

respectively, sitting at their highest since October 2008.

The 30-year JGB yield touched a one-month

high of 2.345%.