TOKYO, April 12 (Reuters) - Japanese government bonds firmed on Wednesday, with the benchmark 10-year yield edging down to a four-month low, taking cues from U.S. Treasury yields and reduced purchases by the Bank of Japan in its bond-buying operations.
The benchmark 10-year JGB yield fell one basis point to 0.025 percent, its lowest since Dec. 5, while 10-year JGB futures added 0.20 point to 150.88 after earlier touching 150.92, their highest since Nov. 15.
U.S. Treasury yields slipped overnight as fresh concerns about the French presidential election and possible U.S. military action against Syria and North Korea spurred safe-haven demand, and continued to drop in Asian trading.
The 10-year Treasury yield stood at 2.285 percent , down from the U.S. close of 2.315 percent on Tuesday.
The Bank of Japan also trimmed its purchases of Japanese government bonds with three to five years left to maturity on Wednesday, buying 350 billion yen of them in its regular operations, down from 380 billion in previous operations.
"Overall, there was limited reaction to the BOJ, as the market focuses on Treasuries, whose yields appear to have moved into a new range," said Tadashi Matsukawa, head of fixed income investment in Tokyo at PineBridge Investments.
In the superlong zone, the 20-year yield fell two basis points to 0.590 percent, its lowest since mid-January, while the 30-year yield lost 3 basis points to 0.805 percent, its lowest since late February.
Reporting by Tokyo markets team; Editing by Sunil Nair