BENGALURU, India — Treasury Secretary Janet L. Yellen said on Thursday that the United States would redouble its efforts to marshal global support to help Ukraine and warned that China would face repercussions if it helped Russia evade American sanctions.
She spoke as top policymakers from around the world gathered in southern India for a meeting that is expected to focus largely on accelerating a global economic recovery after three years of international crises. The warning to China underscores how the impact of the war continues to reverberate, straining ties between the world’s two largest economies as they were attempting to stabilize their relationship.
“We have made clear that providing material support to Russia or assistance with any kind of systemic sanctions evasion would be a very serious concern for us,” Ms. Yellen said. “We will certainly continue to make clear to the Chinese government and the companies and banks in their jurisdiction about what the rules are regarding our sanctions and the serious consequences they would face for violating them.”
Ms. Yellen declined to describe specific U.S. intelligence about Russian attempts to avoid sanctions but the Treasury Department has pointed to attempts by Russia to seek assistance from China to supply it with items such as semiconductors which face trade restrictions.
Trade data shows that China, along with countries including Turkey and some former Soviet republics, has stepped in to provide Russia with products that civilians or armed forces could use, including raw materials, smartphones, vehicles and computer chips. Biden administration officials have expressed concern that China could provide Russia with lethal weapons, however China does not appear to have done so yet.
The United States has cracked down on some of the companies and organizations supplying goods and services to Russia. In January, it imposed sanctions on a Chinese company that had provided satellite imagery to the Wagner mercenary group, which has played a large role in the battle for eastern Ukraine. In December, it added two Chinese research institutes to a list of entities that supply the Russian military, which will restrict their access to U.S. technology.
On Thursday, Ms. Yellen made clear that the United States would crack down on sanctions evasion. “We are seeking to strengthen sanctions and to make sure we address violations of sanctions,” she said.
The effectiveness of sanctions on Russia continues to be a subject of intense debate, as recent forecasts from the International Monetary Fund suggested that its economy is performing better than expected.
But Ms. Yellen offered a dark assessment of Russia’s economy, arguing that sanctions imposed by the United States and other Western nations were working to isolate the Kremlin, drain the country of talent and sap its productive capacity. Still, the United States continues to view the conflict as the biggest threat to the global economy, and Ms. Yellen made clear that the Biden administration is prepared to continue punishing Russia for its incursion.
Ms. Yellen said that the United States plans to unveil additional sanctions on Russia and that it is working with its allies to devise ways to tighten restrictions already in place.
“We will stand with Ukraine in its fight — for as long as it takes,” Ms. Yellen said at a news conference as finance ministers from the Group of 20 nations, which include Russia and China, convened for two days of meetings.
The Treasury secretary said that the United States had already provided more than $46 billion in security, economic and humanitarian assistance to Ukraine and that another $10 billion in economic support would be delivered in the coming months. Ms. Yellen also called on the I.M.F. to “move swiftly” with a fully financed loan package for Ukraine. The I.M.F. last year approved more than $1 billion in emergency financing to Ukraine to mitigate the economic impact of the war.
“Continued, robust support for Ukraine will be a major topic of discussion during my time here in India,” Ms. Yellen said.
The United States hopes to include a condemnation of Russia’s actions in Ukraine in the joint statement, or communiqué, that the finance ministers are set to release later this week. However, it is not clear if a decisive statement will be possible because Russia is a member of the G20 and India, which is hosting the event, continues to buy large quantities of Russian oil.
Despite the urgency to address the crisis in Ukraine, Ms. Yellen offered an upbeat assessment of the global economy, which has begun to recover. While she acknowledged that headwinds remained, she said the world was on more stable footing than last fall, when many were forecasting a global recession.
“It’s fair to say that the global economy is in a better place today than many predicted just a few months ago,” Ms. Yellen said, pointing to a recent global growth upgrade from the I.M.F.
She added that the United States economy was proving to be resilient, with inflation moderating while the labor market remains strong.
During their meetings on Friday and Saturday, finance ministers are also expected to discuss ways to alleviate the debt crises facing many developing countries. Officials are also expected to put pressure on China, which has become one of the world’s largest creditors, to demonstrate more willingness to let more countries restructure their debt.
“I will continue to push for all bilateral official creditors, including China, to participate in meaningful debt treatments for developing countries and emerging markets in distress,” Ms. Yellen said.
It was unclear if Ms. Yellen would have any meetings with Chinese officials this week. She said that keeping lines of communication open about macroeconomic issues remained important.
“I certainly expect that we will resume discussions,” Ms. Yellen said, adding, “I don’t have a specific time frame in mind but I think it’s important to do so.”
Ana Swanson contributed reporting.