Economic risks from Japan's earthquake, tsunami and nuclear crisis have increased in the past week, Moody's said, but it expects the Japanese economy to resume growth in the second half of the year.

Moody's currently expects the Japanese economy to experience a brief recession in the second quarter of 2011 and to emerge from it right after. As a result, gross domestic product would still grow 1 percent this year, down from the 1.4 percent forecast before the disaster, the agency said.

In 2012, however, Moody's sees reconstruction supporting economic expansion of 2.3 percent, up from its previous forecast of 1.9 percent.

"The key assumption underlining this base case is a speedy containment of the nuclear problem," Moody's said in a statement.