Sony Corp. Chairman Nobuyuki Idei said Sunday he thinks the Japanese currency has been overvalued and he would not be surprised if the yen -- which trades at around 130 to the dollar now -- falls to the 150-160 range.

"A weak yen is the only effective (economic stimulus) measure. The yen has long been overvalued, considering labor productivity and other economic data," Idei told reporters.

Idei, in New York to attend the World Economic Forum, defended weakening the yen, which he said brings "lots of economic benefits," including cheaper costs for many Asian debtor countries that have borrowed money from Japan and manufacturers that buy Japanese industrial parts.

"The weakened yen is a good thing in many ways," he said.

Idei also dispelled concerns that Prime Minister Junichiro Koizumi's economic reforms may be thwarted by the plunge in the support ratings for his Cabinet following his sacking of controversial but popular former Foreign Minister Makiko Tanaka.

Various Japanese media surveys show Koizumi's support ratings plunged to under 50 percent after Tanaka was let go last Tuesday, from the upper 70 percent range prior to her dismissal.

Idei said relying on a high support rating for reform is not necessarily a good thing.

"With a 70 percent support rating, you feel rather uneasy. You get a good deal of steam off if the support rate gets down to the 40 percent level," he said.