BEIJING — Chinese President Xi Jinping promised Friday to set high standards for Beijing’s sweeping infrastructure-building initiative as fellow leaders praised the effort despite worries it is saddling some countries with too much debt.

Xi avoided mentioning debt in a speech at a Belt and Road forum celebrating his signature foreign initiative. But he promised changes in response to complaints about costs, dubious payoffs from the projects and possible environmental damage.

Beijing wants “open, green and clean cooperation” with “zero tolerance for corruption,” Xi said.

Developing countries have welcomed the initiative, launched in 2013, to expand trade by building roads, ports and other facilities from Asia through Africa and the Middle East to Europe. But some governments are struggling to repay Chinese loans, fueling complaints poor countries are being pushed into a “debt trap.”

The United States, Japan, India and Russia have chafed at the expansion of Beijing’s strategic influence with the building of trade and political networks centered on China.

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Despite that, Russian President Vladimir Putin on Friday praised the initiative, saying it dovetails with the goals of a Russian-promoted market with four of its neighbors, the Eurasian Economic Union.

Malaysian Prime Minister Mahathir Mohamad, who had suspended plans for a Chinese-built railway and other projects due to their cost, said he was “fully in support.”

Prime Minister Imran Khan of Pakistan, one of China’s closest allies, said Belt and Road has produced “substantial progress” in increasing power supplies and other areas.

The U.N.’s secretary-general, Antonio Guterres, said Belt and Road projects could help turn the balance in mitigating climate change.

Xi’s government is trying to revive the initiative’s momentum after the number of new projects plunged last year. That came after Chinese officials said state-owned banks would step up scrutiny of borrowers and some governments complained projects do too little for their economies and might give Beijing too much political influence.

Other countries including Thailand and Nepal have canceled or scaled back projects while Ethiopia and others have renegotiated debt repayment.

Xi promised changes to forestall corruption and environmental damage, and sought to allay worries Beijing is reaping most of the economic benefits and gaining power at the expense of countries involved.

The Belt and Road is “not an exclusive club” and promotes “common development and prosperity,” Xi said. He said Belt and Road will embrace international standards for project development, purchasing and operations.

China issued “debt sustainability” guidelines Thursday for assessing debt risks to borrowers that the Ministry of Finance said are based on standards of the International Monetary Fund and other international institutions.

Finance Minister Liu Kun said the guidelines, intended to “prevent and solve debt problems,” would classify countries by risk based on productivity, economic growth and other factors.

Other leaders attending the forum included Aung San Suu Kyi, state councilor for Myanmar, Ethiopian Prime Minister Abiy Ahmed and leaders or envoys from Germany, Italy and Greece.

Xi said Beijing wants to encourage cooperation on health, water resources, agriculture and technology. He promised scholarships for students from Belt and Road countries.

Chinese lenders have provided $440 billion in financing, the country’s central bank governor, Yi Gang, said Thursday without giving details on repayments or risks of defaults.

In addition, some 500 billion yuan ($75 billion) has been raised in Chinese bond markets, according to Yi.

The United States, Japan and other wealthy countries also finance construction in a region the Asia Development Bank says needs $26 trillion of investment through 2030 to keep economic growth strong.

In March, Italy became the first member of the Group of Seven major economies to sign an agreement to support Belt and Road.

Belt and Road countries also include many of the poorest and most indebted in Africa and Asia.

About one-quarter of the 115 governments that have signed agreements to support the initiative have foreign debt equal to at least 75% of their annual economic output, according to Moody’s. Mongolia is the most extreme at 240 percent. Egypt, Indonesia and Pakistan all are above 50%.

None is in immediate danger of default, but Belt and Road economies tend to have higher debt than average, weaker financial flows and more vulnerability to economic shocks, said Lillian Li, a Moody’s vice president.

Borrowing “more external funds will be more dangerous to themselves as well as to the lending countries,” Li said in an interview.

There’s a limit to how much Xi’s government might change the initiative because Beijing still wants to increase its influence and generate work for Chinese industries, Tom Rafferty of the Economist Intelligence Unit said in a report ahead of Friday’s forum.

One element to watch will be whether Beijing tries to enhance the appeal of Belt and Road by making it more like the World Bank or other multinational organizations, he said.

“This has the potential to generate further tensions with the U.S.,” Rafferty said.

Associated Press writer Christopher Bodeen contributed.