A man looks at his watch as he passes an electronic board displaying a graph of currency rates outside a brokerage in Tokyo.

Tokyo - Tokyo stocks ended an erratic session 0.36 percent higher Wednesday, helped by a firmer dollar as investors turn their attention to US Federal Reserve's latest monetary policy meeting.

The benchmark Nikkei gained 51.25 points to 14,462.52 while the Topix index of all first-section issues slipped 0.14 percent, or 1.61 points, to 1,164.33.

Shares in Japan Display - the world's biggest maker of screens for smartphones and tablets and a key Apple supplier - plunged on their Tokyo debut, following a $3.2 billion initial public offering.

The Nikkei opened higher, tracking gains on Wall Street despite news that Russian President Vladimir Putin signed a treaty absorbing Crimea following its controversial weekend vote to break away from Ukraine.

But the index spent the rest of the day see-sawing in line with the yen.

In afternoon forex trade, the dollar bought 101.53 yen, against 101.42 yen in New York - having fallen as low as 101.26 yen at one point in Tokyo.

“There is not necessarily any 'doom and gloom' sentiment in the market, as there has been some selective dip-buying in recent days,” said an equity trading director at a foreign brokerage.

“But clearly there is a lack of overtly bullish sentiment as a result of there being no catalysts.”

Investors were waiting the outcome of a two-day meeting of the Fed's policy-setting committee, the first chaired by new chief Janet Yellen.

While analysts expect a further cut in the bank's stimulus programme as the economy picks up, they will be focusing on Yellen's follow-up news conference to see if she gives any clues about future policy plans.

There was little reaction to data showing Japan ran a trade deficit for the 20th consecutive month in February, although the shortfall was well down from a record deficit in January.

Japan Display, which slumped 22 percent at one point, ended down 15.2 percent at 763 yen, with one analyst describing the losses as a “disaster”.

Sony rose 0.63 percent to 1,731 yen, Toyota slipped 0.75 percent to 5,508 yen, while Fast Retailing, operator of Uniqlo clothing stores, climbed 1.68 percent to 36,190 yen. - Sapa-AFP