The official Purchasing Managers' Index of China's service sector hit 55.2 in May, down 0.9 point from a month earlier, the National Bureau of Statistics said on Sunday. [File Photo]

China's non-manufacturing activities in private and export-oriented firms unexpectedly strengthened in May, which may give policy makers worried about the economy some breathing space.

The HSBC and Markit Economics' headline Business Activity Index, which weighs performance of private service firms, hit a 19-month high of 54.7 in May from April's 54.1, the bank said yesterday. A reading above 50 signals expansion.

The survey participants attributed the increase to securing new business, which signaled a marked growing activities.

"The growth in service activities picked up in May thanks to sustained gains in new business," said Qu Hongbin, chief economist for China at HSBC. "This should reduce the fears of a sharp economic slowdown."

Companies also continued to express strong confidence over the one-year business outlook even amid the current weak performance in the overall economy.

But state-owned service enterprises reported their activities weakened last month.

The official Purchasing Managers' Index of China's service sector hit 55.2 in May, down 0.9 point from a month earlier, the National Bureau of Statistics said on Sunday.

"Service activities weakened further due to sluggish demand from both home and abroad," the bureau said. "But encouragingly, the index remained above the point indicating expansion, and service providers exhibited confidence for the future."

On Monday, China's Minister of Commerce Chen Deming reiterated: "If the growth continues to weaken, the government will take a variety of measures to ensure stable growth in domestic consumption, domestic investment and international trade."

China's economy grew 8.1 percent year on year in the first quarter, the slowest in nearly three years. Some economists expect the growth rate to slip below 7.5 percent in the current quarter.

China's official manufacturing Purchasing Managers' Index, which measures operational conditions in factories, fell to a five-month low of 50.4 last month from April's 53.3 - the first drop this year.

China has unveiled new stimulus measures to boost the economy.