Japan's automakers are "suffering very severely" from the floods in Thailand while confronted at the same time with the yen's appreciation, said Toshiyuki Shiga, chairman of the Japan Automobile Manufacturers Association.
The carmakers have shut their factories in Thailand since mid-October and the "situation will continue" in November, he said.
"Japanese automakers faced the March 11 earthquake and tsunami which resulted in supply chain disruptions and power shortages," Shiga, who is also chief operating officer of Nissan Motor Co, said.
"We stayed focused and recovered from the disaster quickly. Unfortunately, we're now facing several difficulties."
Thailand's worst floods in half a century have inundated about 10,000 factories and output losses are spreading beyond the country as supplies of components for cars and computers are disrupted.
Japanese automakers are losing production of about 6,000 cars a day because of the floods.
The strong yen, high corporate taxes and slow progress toward trade agreements have put Jap-an's position as an automotive manufacturing base at risk, Shiga said.