A tax of 2,400 yen ($19.92) per tonne of carbon emitted from fossil fuels would cost each household roughly 2,100 yen a year.

According to the ministry's Internet survey conducted last week, 77.7 percent of 1,442 respondents said they would accept the tax while 17.3 percent would not, Kyodo news agency said.

Asked if they favoured imposing the tax in proportion to the amount of carbon emissions, 65.8 percent said they did.

Ministry officials were unavailable for comment.

Japan, the world's second-largest economy, is struggling to cut emissions in line with tough targets set by the Kyoto Protocol. Emissions have in fact risen 8 percent since 1990 instead of dropping the pledged 6 percent.

One of the least efficient sectors is private households, where emissions have risen 28.8 percent from 1990 levels because of an increase in the number of appliances, such as computers.

A previous attempt to impose an environment tax was rejected by parliament.