BEIJING — China will ensure that developing countries do not borrow too much of its debt. China will pursue more clean, green projects. China will improve the level of transparency in its deals with countries around the globe.

Those were among the pledges by Chinese President Xi Jinping on Friday to 37 heads of state and top officials from 100 countries gathered in Beijing to hear updates on Xi’s signature foreign policy, a vast, $1 trillion international development project known as the Belt and Road.

But Xi’s message — once triumphant — was distinctively conciliatory.

Two years after the Chinese leader launched the initiative to exuberant fanfare, foreign diplomats and international observers say they have sensed a shift in tone — perhaps even downsized ambitions — as China faces stinging international criticism and rising questions about the project’s fiscal and environmental feasibility.

“We must adhere to the concept of openness, greenness and cleanliness,” Xi said Friday as he defended his project, which envisions ports, highways, rail lines and other links across Asia and beyond.

But with investments across Asia stalling or scaled back and the Chinese economy slowing, Beijing has had to dampen its propaganda — and quietly tighten up the flow of investments into the Belt and Road initiatives, analysts say.

“The Belt and Road has most certainly been a learning process,” said Zha Daojiong, a professor at the Institute of South-South Cooperation and Development at Peking University. “Some scaling back is normal. The scale — including the number of entities that formally subscribe to the initiative — is less significant than the quality of the projects.” 

As criticism grew last summer, Xi instructed officials to clean up the program with a traditional Chinese painting metaphor. If the Belt and Road was painted with freehand technique before, he said, it should now be done with detailed brushstrokes. 

Last month, Chinese Foreign Minister Wang Yi publicly welcomed “constructive opinions” about what China could do better. Days later, China’s No. 2 leader, Premier Li Keqiang, made just a passing reference to the Belt and Road in a speech to Asian heads of state and financiers as he promised reform for China’s trade practices.

This week, along Beijing’s boulevards, billboards for the forum promise “extensive consultations” and “mutual learning” between China and its partners.

State media, meanwhile, has been relatively muted compared to 2017, when the propaganda machine unleashed a slew of triumphant media coverage, English-language cartoons and singalong music videos extolling how China’s financial largesse was benefiting mankind.

Mentions of Belt and Road in the Communist Party’s agenda-setting People’s Daily newspaper have fallen sharply in the past year, suggesting an effort by central leaders to downplay the program, said Minxin Pei, a professor of government at Claremont McKenna College.

“We see a decrease in the amount of effusive rhetoric because there’s not really that much good news to report,” Pei said.

Chinese government data suggests China may be dialing back its overseas investments. In the first quarter of 2019, China’s nonfinancial investments in Belt and Road countries grew 4 percent compared to 22 percent a year prior, its lowest rate in years, Bloomberg News reported.

While the Belt and Road plan has caught flak from expected quarters — Secretary of State Mike Pompeo and top Pentagon officials have sounded dire warnings about China ensnaring smaller countries in “debt traps” — Chinese officials are perhaps more alarmed that some traditional partners have wavered on their commitments.

In the past year, newly elected governments in Malaysia and Pakistan have sought to renegotiate Chinese loan packages. Myanmar and Nepal have backed away from agreements for China to build dams, ports and power plants, questioning whether the debt burden would be too great.

China hit a public relations quagmire in late 2017 when Sri Lanka, struggling to make debt payments, handed control over a port and swath of territory for 99 years to China. The concession carried historical echoes of China’s humiliating transfer of Hong Kong to colonial Britain in the 19th century, and reinforced U.S. claims that China is a new colonial power in the making.

Meanwhile at home, Chinese intellectuals have questioned privately — and in rare instances, publicly — the wisdom of funneling national riches to far-flung countries at a time of slowing economic growth and rising unemployment.

Last year, Xu Zhangrun, an influential law professor at Tsinghua University, rebuked Xi in a widely read essay for playing the “flashy big-spender” who invested in vanity projects in the Middle East when more than 100 million Chinese lived below the poverty line. Tsinghua suspended Xu from teaching this month, but similar criticisms have surfaced on Chinese social media and circulate frequently among Chinese intellectuals, said the Claremont McKenna professor Pei.

“To a person, they think this is folly,” Pei said. “The government isn’t unaware of the criticisms, but because of political conformity and the climate of fear in China, very few would dare to say anything negative.”

Still, China has forged ahead. Despite notable exceptions including the United States, India, Germany and France, there are now 126 countries involved or pledging support for China’s Belt and Road plans.

Last month, Xi scored a diplomatic coup on a trip to Rome as Italy signed an agreement to become the first Western European participant in the Belt and Road despite behind-the-scenes lobbying by U.S., French and German officials.

Nadège Rolland, a scholar at the National Bureau of Asian Research, said the Chinese government will “refine” the rough edges of the Belt and Road program, not abandon it.

The project, which has been closely linked to Xi’s political legacy and enshrined into China’s national constitution since 2017, is fundamentally aligned with the Communist Party’s objective of expanding overseas markets for China and expanding its economic and geopolitical footprint, she said.

“You can’t differentiate the Belt and Road with China’s overall foreign policy, which is to push itself to the center stage of the world,” Rolland said. “It’s wishful thinking by people in the U.S. and Europe that Belt and Road will not last, or that China will hit a wall. It hasn’t.”