The Tokyo stock market opened the month moderately higher Monday, but the rally soon fizzled, dashing hopes that the Nikkei average would soon hit 12,000.

Initially, the market reacted calmly to the May 31 lowering of Japan's sovereign debt rating by Moody's Investors Services Inc. and the realignment of Morgan Stanley Capital International indexes the same day.

Although concerns over the potentially demoralizing factors have eased to an extent, the Tokyo market appears set to continue struggling, especially given the continued weakness in New York share prices and the dollar.