Japan is promising emergency assistance to Japanese companies whose plants and subsidiaries in Thailand have been damaged or disrupted by massive flooding in that country.

The floods are already disrupting supply lines and slowing production at some of Japan's biggest companies, just as they recovered from slowdowns caused by the March 11 earthquake and tsunami.

Officials said Tuesday the assistance will include expanded loan guarantees and trade insurance programs. The Bank of Japan may also guarantee some Thai government loans.

Major Japanese firms including Toyota, Honda and Sony have important production facilities in Thailand, some in a series of industrial parks north of the city that have been inundated by Thailand's worst flooding in 50 years.

Toyota announced this week it is cutting back automobile production in Japan because of supply disruptions from Thailand, while Honda says it car assembly plant in Thailand is under water.