triple blow of earthquake, tsunami and one of Japan's worst nuclear accidents is set to damage the world's third largest economy, possibly more deeply and for longer than initially expected.

triple blow of earthquake, tsunami and one of Japan's worst nuclear accidents is set to damage the world's third largest economy, possibly more deeply and for longer than initially expected.

Power outages and possible tax rises are likely to hurt companies and households and could outweigh the mild economic aftershock from the 1995 Kobe earthquake, given that oil prices and the yen are stronger and Japan's debt pile is much bigger.

Rolling blackouts will start Monday, affecting businesses and households as the country grapples with its worst crisis since World War Two. More than 1 million people are without water or power and towns have been wiped off the map.

Already saddled with debt that is double the size of its $5 trillion economy and threatened by credit downgrades, the government is discussing a temporary tax rise to fund relief work.

Japan's economic growth is in a better profile than it was when the Kobe quake struck. But many say a noticeable hit to GDP, which was only just recovering from contraction at the end of 2010, is likely to be felt over the next several months.

"When we talk about natural disasters, we tend to see an initial sharp drop in production... then you tend to have a V-shaped rebound. But initially everyone underestimates the damage," said Michala Marcussen, head of global economics at Societe Generale.