The US dollar has fallen to its lowest level against the yen in four years.
The dollar has fallen yet again
After increased optimism in Japan at the turn of the financial year, the yen rose as far as 104.52 per dollar, its highest level since June 2000.
The yen then fell back slightly on speculation that the Bank of Japan had intervened and sold off some of its stocks.
But not before a number of exporters fell on Japan's Nikkei index.
By afternoon trading in Tokyo it was down 64.38 points or 0.55% to 11,629.3.
The Nikkei did however eventually recover to end up 0.19% or 21.71 points to 11.715.39.
"My sense is that right now the economy in Japan is really recovering and with the Nikkei poised to break 12,000, one should be looking for a much lower dollar/yen from now, maybe in the lower side of the 100-105 range," said Lee Boon Keng, a strategist with DBS Bank in Singapore.
The yen's rise reverses recent gains by the recovering dollar.
Analysts said the Nikkei was also experiencing traditional year end profiting.