Japan intervened in currency markets on Thursday to curb the yen's gains that officials fear threatened to derail the economy's recovery from a slump triggered by a massive earthquake in March.

Finance Minister Yoshihiko Noda said Japan acted on its own and aimed to stem speculative and disorderly currency moves.

Noda told a news conference he expected the Bank of Japan to take appropriate action. He declined to comment on the size of the intervention or say what currencies Japan bought.

The central bank, which started its policy meeting on Thursday would announce its policy decisions later in the day.

The action that followed days of official warnings that the currency, largely driven by broad dollar weakness, has passed levels that the export-reliant economy could live with, pushed the yen down to about 78.30 to the dollar from a level of around 77.

Some currency traders braced for further dollar declines should U.S. payroll data on Friday heighten concerns about the health of the U.S. economy. That could increase the chance of Japanese government intervention and make it more likely that the Bank of Japan will ease policy at a meeting ending on Friday.

Suzuki Motor Corp. executive vice president Toshihiro Suzuki said on Wednesday it was "very sad" that no one was taking action against the strong yen, adding to a chorus of Japanese business leaders calling for action to weaken the currency.

Japan last intervened in concert with the Group of Seven in March, when expectations of fund repatriation after the earthquake pushed the yen to a record high.

The yen surged nearly 5 percent in the past month and on Monday came close to a record high against the dollar.

(Writing by Tomasz Janowski; Editing by Muralikumar Anantharaman)