The US has recently begun seeing "disturbing" trendlines in China's support for Russia's military and there are signs that Beijing wants to "creep up to the line" of providing lethal military aid to Russia without getting caught, the media reported.
The officials would not describe in detail what intelligence the US has seen suggesting a recent shift in China's posture, but said US officials have been concerned enough that they have shared the intelligence with allies and partners at the Munich Security Conference over the last several days, the CNN reported.
Secretary of State Antony Blinken raised the issue when he met with his Chinese counterpart, Wang Yi, on Saturday on the sidelines of the conference, officials said.
"The Secretary was quite blunt in warning about the implications and consequences of China providing material support to Russia or assisting Russia with systematic sanctions evasion," a senior State Department official told reporters, CNN reported.
Vice President Kamala Harris also alluded to China's support for Russia during her speech in Munich.
"We are also troubled that Beijing has deepened its relationship with Moscow since the war began," Harris said Saturday. "Looking ahead, any steps by China to provide lethal support to Russia would only reward aggression, continue the killing, and further undermine a rules-based order."
Officials said the US is seeing China publicly trying to present itself as a proponent of peace - Wang said in Munich on Saturday that Beijing would be introducing a "peace plan" for Ukraine and Russia - and maintain relationships with Europe, while at the same time quietly aiding Russia's war effort and considering the provision of lethal aid, CNN reported.
"This warfare cannot continue to rage on. We need to think about what efforts we can make to bring this warfare to an end," Wang said at the conference.