Finance Minister Hiroshi Mitsuzuka said Friday that authorities are prepared to act given the continued depreciation of the yen against the dollar on foreign exchange markets.

The dollar was changing hands at 129.67-129.69 yen at 2 p.m. in Tokyo, and dealers said the U.S. currency could break through the 130 yen line.

Mitsuzuka told reporters said that sudden movements in currency rates, in this case depreciation, are undesirable. "If the yen depreciates excessively, we must take appropriate action, and we are currently monitoring the market with preparations to act" if necessary, he said.