HONG KONG — China is planning new steps that could put a stop to making Bitcoin there, a move that could cut off one of the world’s largest sources of the popular but unstable cryptocurrency.

The National Development and Reform Commission, China’s top economic planning body, this week added cryptocurrency mining to a list of about 450 industries that it proposes to eliminate. If the move is approved, local governments in China will be prohibited from supporting makers of Bitcoin and other digital currencies through subsidies or other benefits.

The commission said it would seek public comment until May 7 before making a final decision.

China was once the world’s largest Bitcoin maker, though rising government pressure has forced many of those who make the cryptocurrency, known as miners, to other countries. Still, a number of Bitcoin miners could remain, especially if local governments ignored the instructions and found a way to prop up local producers, people in the business say.

“It is categorized as an industry that is not encouraged or allowed to expand, but it is not a ban,” said Zhao Qianjie, a former executive at BTCChina, which was China’s first cryptocurrency exchange.