The headquarters of Sony Corp in Tokyo. The company announced last month that it will cut 10,000 jobs worldwide. Tomohiro Ohsumi / Bloomberg

Japan's jobless rate rose for the first time since January and retail sales fell for a second month, underscoring concern that the country's economic recovery will lose momentum in the face of gains in the yen and Europe's debt crisis.

Its unemployment rate increased to 4.6 percent in April from 4.5 percent the previous month, the statistics bureau said on Tuesday in Tokyo. Retail sales fell 0.3 percent from March, the Trade Ministry reported.

Sony Corp is among the manufacturers that have announced job cuts that may weigh on an economy that relied on consumer spending for most of its growth in the first quarter. The expansion may slow as boosts from earthquake reconstruction and government incentives to spur spending fade and Europe's sovereign-debt crisis and austerity measures cap exports.

"Employment conditions are not improving," said Masamichi Adachi, senior economist at JPMorgan Securities in Tokyo and a former central bank official. "Recent economic indicators and a deterioration in financial markets suggest that strong growth cannot be maintained."

Bank of Japan board members said last month they need to counter the mistaken perception that central bank asset purchases will automatically increase, a record of the BOJ's April 27 meeting released on Monday showed. Policymakers have to use stimulus measures should the yen advance "significantly", according to Hiroshi Miyazaki, chief economist at Shinkin Asset Management Co in Tokyo.

The overall unemployment results are "not that good", said Azusa Kato, an economist at BNP Paribas SA in Tokyo. "Today's employment data suggested a mismatch of jobs and geographic areas is widening."

There has been an increase in construction jobs as reconstruction projects in the disaster-struck north have started, pushing up labor demand and costs in those regions, Kato said.

At the same time, a succession of Japanese manufacturers have plans to cut jobs this year. Both Sony and NEC Corp have announced cuts of 10,000 workers worldwide.

Shares in Renesas Electronics Corp fell on Monday to the lowest level on record after the company was said to be planning to eliminate 10,000 jobs and raise 100 billion yen ($1.3 billion) under the latest draft of a restructuring plan.

The yen has climbed about 5 percent against the dollar from this year's low in mid-March, weighing on export sales and profits for manufacturers. The currency was at 79.56 as of 9:15 pm on Tuesday in Tokyo.

Japanese Vice-Finance Minister Takehiko Nakao said on Tuesday that the finance ministry will take action if necessary, suggesting that the door is open to further government intervention to weaken the currency.