Tokyo stocks up 0.70% by break

Tokyo stocks climbed 0.70 percent Monday morning, a seventh successive rise as a weak yen boosted exporters.

The Nikkei 225 index at the Tokyo Stock Exchange added 142.61 points to 20,407.02 by the break.

The Topix index of all first-section issues was up 0.67 percent, or 11.10 points, at 1,658.95.

"Inflation is speeding up a little in the United States, and we can see the intention to raise rates sometime this year," said Shoji Hirakawa, chief equity strategist at Okasan Securities.

"When we consider the US versus Japan, rates will be higher in the States. Japan's rate hikes and tapering will be further into the future," he told Bloomberg News.

The dollar surged on Friday on an unexpected jump in US core inflation in April and remarks by Federal Reserve chief Janet Yellen in support of a rate hike this year.

The dollar was at 121.65 yen in midday trade on Monday, up slightly from 121.52 yen in New York and sharply up from 120.71 in Tokyo earlier Friday.

A weak yen is positive for Japanese exporters as it makes them more competitive abroad and inflates profits when repatriated.

Auto makers were higher, with Toyota up 1.38 percent at 8,462 yen and Honda rising 1.41 percent to 4,182.5 yen.

Toshiba fell 0.51 percent to 408.9 yen after announcing Friday that it was expanding an accounting probe to its television, memory chip, and computer divisions in addition to infrastructure projects after earlier warning the investigation would take a toll on its balance sheet.

Tokyo Electric Power, the operator of the tsunami-crippled Fukushima nuclear plant, soared 5.12 percent to 615 yen on news that it and Japanese trading house Mitsubishi jointly won a 300 billion yen contract for a power and water project in Qatar.