According to US sources, US National Security Adviser Jake Sullivan will meet with China’s senior diplomat Yang Jiechi in Rome on Monday and will emphasize the economic consequences Beijing will suffer if it aids Russia in its war in Ukraine.

According to one US source, Sullivan would warn China of the global isolation it may face if it continues to assist Russia.

In recent weeks, officials from the US and other nations have tried to make it plain to China that siding with Russia might have ramifications for trade flows, the development of new technology, and expose it to secondary penalties.

Chinese firms that disobey US export prohibitions to Russia risk losing access to the American equipment and software they use to manufacture their goods, according to US Commerce Secretary Gina Raimondo.

It will be Sullivan’s first public encounter with Yang since closed-door talks in Zurich in October, which aimed to defuse tensions following an ugly public exchange in Alaska a year ago.

China is the world’s largest exporter, the European Union’s largest trading partner, and the United States’ top foreign supplier of products, so any restrictions on Chinese trade might have a negative impact on the US and its allies’ economies.

According to Reuters, US sources told Reuters on Sunday that Russia had approached China for military weapons following its invasion, raising concerns some Biden administration officials that Beijing may hinder Western attempts to support Ukraine by assisting Moscow’s military.

On Sunday, Sullivan told CNN that Washington was keeping a careful eye on China’s economic and material support for Russia.

“We are speaking directly and privately with Beijing that large-scale sanctions evasion activities or support to Russia to backfill them would undoubtedly have consequences,” he added.

“We will not allow that to happen, and we will not allow any government, anywhere in the globe, to provide a lifeline to Russia through economic sanctions.”

Relations between the two countries, which were already at an all-time low, suffered a further hit last month when presidents Xi Jinping and Vladimir Putin proclaimed an improved “no boundaries” strategic alliance just weeks before the invasion of Ukraine.

Although Xi last week called for “maximum restraint” and expressed concern about the impact of Western sanctions on the global economy, amid growing signs that they are limiting China’s ability to buy Russian oil, Beijing, a key trading partner of Russia, has refused to call Moscow’s actions an invasion.

While contributing billions of dollars in military and humanitarian aid to Ukraine, Washington and its allies have placed sweeping, unprecedented sanctions on Russia and restricted its energy imports.