Tokyo shares open down ahead of Yellen speech

Tokyo shares opened lower on Friday as markets awaited remarks by Federal Reserve boss Janet Yellen with hopes that she will drop clues about the outlook for US interest rates.

Many investors are taking a wait-and-see stance ahead of Yellen's address at an annual symposium in Jackson Hole, Wyoming, analysts said.

The benchmark Nikkei 225 index fell 1.07 percent, or 177.34 points, to 16,378.61 in mid-morning trade, while the broader Topix index of all first-section shares was off 1.10 percent, or 14.30 points, at 1,289.97.

In forex markets, the dollar stood at 100.44 yen, weakening from 100.55 yen in New York.

Yellen's speech comes amid concerns that leading central bankers -- having pushed interest rates to ultra-low and even negative levels -- have still proven unable to convincingly reverse a broad economic slump.

Analysts believe Yellen might come across as relatively optimistic, after recent remarks by Fed Vice Chair Stanley Fischer, whose views are usually in line with Yellen's.

Fischer said that the Fed was close to its policy targets on unemployment and inflation, and that he expects US growth to pick up in the coming quarters.

"You can't take on risk ahead of important events," like Yellen's speech, Takashi Ito, a Tokyo-based equity strategist at Nomura Securities, told Bloomberg News.

"There are two views on what she'll say; either that she'll take a step forward in her reference to the rate hike, or she won't mention it at all.

"It's difficult to predict. If she does make more hawkish comments the market could be chaotic in the short term," he added.

Shortly before the Tokyo market opened, the Japanese government said consumer prices in July dropped for a fifth straight month in the latest blow to Tokyo's faltering war on deflation.

The 0.5 percent decline in July was worse than the 0.4 percent average fall expected by economists.