TOKYO (Kyodo) -- Tokyo stocks rose Thursday, with the benchmark Nikkei index briefly surging over 4 percent, as investors' wariness eased on media reports that Iran was attempting to reach a cease-fire agreement with the United States.

The 225-issue Nikkei Stock Average ended up 1,032.52 points, or 1.90 percent, from Wednesday at 55,278.06. The broader Topix index finished 69.00 points, or 1.90 percent, higher at 3,702.67.

On the top-tier Prime Market, the main gainers were mining, oil and coal product, and bank issues.

The U.S. dollar briefly weakened to the mid-156 yen range in Tokyo, as dollar buying by market players seeking safer assets subsided on hopes for a halt to the U.S.-Israeli strikes on Iran.

At 5 p.m., the dollar fetched 157.25-27 yen compared with 156.96-157.06 yen in New York and 157.44-47 yen in Tokyo at 5 p.m. Wednesday.

The euro was quoted at $1.1604-1606 and 182.48-52 yen against $1.1628-1638 and 182.66-76 yen in New York and $1.1615-1616 and 182.89-93 yen in Tokyo late Wednesday afternoon.

The yield on the benchmark 10-year Japanese government bond ended up 0.045 percentage point from Wednesday's close at 2.155 percent, as the debt, seen as a safe-haven asset, was sold following the rise of the Nikkei stock index.

Most sectors rose, tracking U.S. counterparts on Wall Street, after the Nikkei lost more than 4,600 points over the past three trading days through Wednesday, giving up gains made after the Liberal Democratic Party won a landslide victory in the snap election on Feb. 8.

While investor concern about the conflict eased, uncertainty over the situation in the Middle East has not been dispelled, with Iranian officials reportedly denying the reports about cease-fire talks, dealers said.

"Market views that stocks had fallen enough, speculation that tensions in the Middle East could ease ...combined with other factors, triggered buybacks" said Toshikazu Horiuchi, equity strategist at IwaiCosmo Securities Co.

Stocks later trimmed their gains following a rise in West Texas Intermediate crude oil futures but rose again on bargain hunting. Heavyweight technology shares and recent decliners led the market.