Toyota Motor Corp. on Tuesday said its net profit for the April-September first half of the year slumped 71.8 percent from a year earlier to 81.58 billion yen (1. 04 billion U.S. dollars), due to the effect of the March 11 earthquake and a persistently strong yen that has dented the automaker's competitiveness and profitability in overseas markets.

The world's largest automaker also said that it logged an operating loss of 32.57 billion yen (417.4 million U.S. dollars), 17.2 percent less than booked a year earlier, on sales totaling 8. 02 trillion yen (102.8 billion U.S. dollars).

In addition the automaker opted Tuesday not to release its earnings for the full fiscal year 2011, saying that supply chain disruptions caused by the floods in Thailand have meant that it is unable to accurately assess its finances.

The firm had previously forecast its full-year revenue to be in the region of 19 trillion yen, with a net income of 390 billion yen, but the figure will be drastically slashed due to impact of the floods in Thailand analysts said.

Toyota said more time will be required before it knows the full impact the floods in Thailand have had on its profits, as factories, not just in Thailand, but other Southeast Asian hubs and as far away as North America, have been disrupted by parts shortages due to the floods.

"More time is needed to complete an assessment of production and sales plans required by the impact of floods in Thailand," Toyota said in its statement on Tuesday.

Toyota's CEO Akio Toyoda said that the Japanese government needs to act swiftly to combat the yen's rise and protect the nation's fragile export sector, which relies on a weak yen to boost profits when overseas revenue is repatriated and to increase the competitiveness of domestic-made goods being exported.

"The Japanese government needs to quickly take action to combat the strong yen," Toyoda said. "Japan's automobile industry may experience not only a 'hollowing out,' but a collapse," remarked the automaker's CEO.