Export growth accelerated in February, before the Tohoku quake and tsunami hit earlier this month, shutting down factories and causing power shortages in a disaster likely to disrupt trade for months.

Overseas shipments rose 9 percent in February from a year earlier, from January's 1.4 percent gain, the Finance Ministry said Thursday. The median estimate of 16 economists was for a 9.1 percent gain.

Japanese stocks had their worst weekly performance since 2008 and the yen reached a postwar high against the dollar last week. The government said Wednesday that damages from the quake may swell to ¥25 trillion, while the Bank of Japan said last week the disaster may hurt business and consumer sentiment and prompt companies to cut factory output.

"With exporters being forced to halt their production due to the earthquake, tsunami and power shortage, exports may not be strong enough to drive the recovery, causing the economy to fall into another lull," said Takeshi Minami, chief economist at Norinchukin Research Institute Co.

Sony Corp., Toyota Motor Corp. and other firms have shut plants and extended production halts. This may impede the economy, which was showing signs of emerging from a fourth-quarter slump.

Sony, Japan's biggest exporter of consumer electronics, suspended some work at five plants in the central and southern regions until March 31 due to trouble getting supplies after power outages, it said Tuesday. Toyota said all domestic car assembly will be stopped until Saturday, while Honda Motor Co. also extended closures.

"It'll be unavoidable that exports will drop in the second quarter because of a decline in production and disruptions to distribution systems," Kiichi Murashima, chief economist at Citigroup Global Markets Japan, said.