(Adds BOJ Sakurai comments, JGB futures close)
TOKYO, Sept 2 (Reuters) - Japanese government bonds fell on Friday, sending longer yields to five-month highs, as the usual buyers stepped back ahead of the U.S. jobs report later in the day while some investors fretted about the Bank of Japan's JGB purchasing plans.
BOJ board member Makoto Sakurai, a former think-tank executive considered an advocate of ultra-loose policy, told Reuters that policymakers will likely focus on refining current policy steps and consider ways to fix a bond yield curve that has flattened too much as a result of its negative interest rate policy.
"I don't think we're now seeing any limit to or facing any problems with having a base money target. There is no need to remove the target," Sakurai said in his first media interview since joining the board in April.
The benchmark 10-year yield rose 2 basis points to minus 0.025 percent after earlier rising as high as minus 0.020 percent, its highest level since March.
September 10-year futures ended down 0.16 point at 151.10.
In the superlong zone, the 20-year yield rose 4.5 basis points to 0.400 percent after earlier touching 0.405 percent, its highest since April 1. The 30-year yield rose 6.5 basis points to 0.505 percent after hitting 0.520 percent earlier, its highest since March 31.
"Buyers don't like this kind of volatility," said Tadashi Matsukawa, head of fixed income investment at PineBridge Investments in Tokyo. "If policy is clarified, then people will step up and buy, but until we know, buyers will be sidelined."
The BOJ's next meeting on Sept. 20-21 coincides with that of the U.S. Federal Reserve.
The U.S. August nonfarm payrolls report is even more in focus than usual, after Federal Reserve Vice Chair Stanley Fischer said last week that the employment data would be a factor in the timing of the central bank's interest rate hikes.
If the Fed opts to tighten, "then maybe the BOJ doesn't need to do anything at all," Matsukawa said. "And ahead of nonfarm payrolls, buyers are quite limited, so that's why we're seeing the long end selling off."
A 30-year 800 billion yen ($7.74 billion) auction next week also weighed on longer maturities.
The BOJ also refrained from buying any longer maturities in its asset purchase programme on Friday. It offered to buy 400 billion yen of 1- to 3-year JGBs, 420 billion yen of 3- to 5-year JGBs, and 430 billion yen of 5- to 10-year JGBs.
Most economists polled by Reuters expect the BOJ to ease policy further this month, though views are divided.
The BOJ declared it will conduct a "comprehensive assessment" on the impact of its stimulus measures at its next meeting. Some JGB market participants have expressed concerns that the BOJ might refrain from buying additional JGBs, or could even reduce its purchases of long bonds.