SHANGHAI — China has spent nearly five years steering an ever-growing stream of hundreds of billions of dollars to a bold plan to gain greater global influence by funding big projects across Asia, Eastern Europe and Africa.

Now, Beijing is starting to tap the brakes.

The value of the deals that Chinese companies are striking under the country’s big global plan — called the Belt and Road Initiative — is smaller than a year ago, according to new data. Chinese officials themselves are sounding a cautious note, voicing worries that Chinese institutions need to be careful how much they lend under the program — and make sure their international borrowers can pay it back.

“Current international conditions are very uncertain, with lots of economic risks and large fluctuations for interest rates in newly emerged markets,” said Hu Xiaolian, the chairwoman of the Export-Import Bank of China, a state-controlled lender that plays a big role in financing the projects, at a forum this month in Shanghai. “Our enterprises and Belt and Road Initiative countries will face financing difficulties.”

China has begun a broad, interagency review of how many deals have already been done, on what financial terms and with which countries, say people close to Chinese economic policymaking, who asked to speak on the condition of anonymity because the effort has not been made public.