TOKYO - Tokyo stocks opened 0.17 per cent lower on Tuesday as caution grew ahead of a policy meeting by the US Federal Reserve.

The Nikkei 225 index at the Tokyo Stock Exchange slipped 25.44 points to 15,363.28 at the start.

Trading was likely to be muted as investors await the start of the two-day US Federal Open Market Committee summit beginning later Tuesday, traders said.

"The Fed's position on the viability of the US economic recovery as well as the winding down of its quantitative easing programme will be under close scrutiny - especially in terms of how it translates to the currency market," said Investrust CEO Hiroyuki Fukunaga.

The US central bank's policy-making body is expected to decide to finally wind up its asset-buying drive, known as quantitative easing, at its two-day meeting. Its announcement on this and interest rates will come at 2am on Thursday in Singapore.

The US dollar was at 107.88 yen early Tuesday, compared with 107.78 yen in New York Monday afternoon.

The euro fetched $1.2699 and 137.00 yen against $1.2699 and 136.86 yen in US trade.

Wall Street stocks finished little changed Monday as the market absorbed losses in petroleum stocks while looking ahead to the Fed meeting.