Japan sold a total of 1.02 trillion yen ($14 billion at Tuesday's rate) worth of its currency over the first four days of November, data from the finance ministry showed Tuesday.

The move followed the 8.07-trillion-yen operation on October 31, the biggest-ever for a single day, after the yen hit a postwar high of 75.32 to the dollar, hitting exporters hard.

It was the first official confirmation of a "stealth" intervention after the move in October, although market players had strongly suspected it.

Traders were unfazed by the disclosure Tuesday with the dollar changing hands at 76.55 yen in Tokyo morning trade, flat from New York late Monday.

The dollar rose above 79.00 yen after the October 31 intervention but soon started sagging again.

Finance Minister Jun Azumi declined to make a direct comment on the November action but said everything remained on the table.

"I will not rule out any options, and I've been telling you that I will act when necessary," Azumi said at a regular news conference.

A senior government official said Tokyo saw stealth intervention as the most effective tactic to stem the yen's rise in November.

"We made a judgement that (stealth intervention) was the most effective way," the official said on condition of anonymity.

The official declined to comment on whether the Japanese government notified US financial authorities of its plan to sell the yen at that time.