HONG KONG — China’s securities regulator has told investment banks operating in the country to avoid publishing politically sensitive research ahead of a twice-in-a-decade meeting of the Communist Party next month, according to people familiar with the matter.

The China Securities Regulatory Commission recently sent an advisory to multiple securities houses, including the domestic units of large international banks, the people said. The mainland China businesses of Goldman Sachs and JPMorgan were among those contacted by the regulator, the people added.