Japanese manufacturers moved swiftly to idle production lines after the global economic downturn sent their exports plunging. Having succeeded in reducing their bloated stockpiles, they are now ratcheting up output again.

Production rose 5.9 percent in May from the previous month, matching April's revised growth, which was the strongest since a record 7.9 percent increase in March 1953, according to the trade and industry ministry.

Production is likely to continue to climb through September on the back of rising exports and economic stimulus measures, predicted Barclays Capital's chief Japan economist, Kyohei Morita.

"However, we have yet to see a self-sustaining economic recovery backed by a turnaround in capital expenditure," he added.

Market expectations had been for a slightly bigger increase of 6.9 percent. Compared with a year earlier, production was down 29.5 percent, underscoring the drastic measures taken by firms since the economic crisis erupted.

Output growth is expected to slow to 3.1 percent in June and to 0.9 percent in July, according to manufacturers' forecasts, the ministry said.

"Production has been rebounding sharply in response to earlier drastic cuts but the momentum is likely to slow in the months ahead," said Hiroshi Watanabe, an economist at the Daiwa Institute of Research.

Production in May was largely boosted by higher output of automobiles, mobile telephones and electronic devices, which had seen a particularly sharp decline in demand due to the global economic slowdown.

While output is now rebounding, it remains much lower than it was before the crisis began.

Production of cars, trucks and buses in Japan was down 41.4 percent in May from a year earlier, while exports were 55.9 percent lower, the Japan Automobile Manufacturers Association said Monday.