The current account surplus narrowed more than expected in March as a record earthquake disrupted the nation's supply chain, curbing exports.

The gap shrank 34 percent from a year earlier to ¥1.68 trillion, the Finance Ministry said Thursday. The median estimate of 12 economists surveyed by Bloomberg News was a 32 percent decline. Exports fell 1.4 percent and imports increased 16.6 percent.

"We expect the trade balance to significantly deteriorate," Takehiro Sato, chief Japan economist at Morgan Stanley MUFG Securities Co. in Tokyo, wrote in a report before Thursday's release. "We expect the current account surplus to narrow temporarily."