China's service sector in October registered its slowest growth in 13 months, as enterprises faced sluggish demand on new orders amid economic downward pressure.

The Caixin Services Purchasing Managers' Index registered 50.8 points in October, down from 53.1 points in September, the lowest reading in 13 months, data showed on Monday.

The sub index for new orders slowed to 50.1 in the previous month, down from 52.4 in September.

The government has pledged to step up support to boost the private sector by rolling out more tax cut measures and alleviating liquidity pressure of the private sector that plays a key role in overall economic growth.