Japan's government bond (JGB) yields have climbed and may be headed even higher, but the yen wasn't likely to follow suit, analysts said.

The benchmark 10-year JGB yield has climbed to around 0.08 percent, after crossing into positive territory in mid-November. Bond yields move inversely to prices.

That's a slight departure from the Bank of Japan's policy, introduced at its late-September meeting, of using yield-curve control as a monetary policy tool, setting its target yield for the benchmark bond at zero.

That target may be headed higher, Sayuri Shirai, a professor at Keio University and a former member of the BOJ, told CNBC's "Street Signs" on Tuesday.

"The BOJ at this moment hasn't done any intervention in the JGB market," she noted. "I think in the first half of next year probably the BOJ should raise their 10-year target from around zero percent to around 1 percent or into a range between zero to 1 percent."

Previously, the BOJ had been willing to intervene to keep the benchmark bond in line with its zero percent target. In mid-November, the central bank offered a special bond buying operation, helping to boost bond prices and bring the benchmark's yield closer to its target.

A rise in U.S. Treasury yields, with the U.S. Federal Reserve widely expected to hike interest rates at its meeting this week, has also pushed up bond yields globally, including Japan's.

Shirai also expected the BOJ would begin tapering its asset purchases under its quantitative easing program, which would also likely push up JGB yields.