The new US ambassador to Germany on Monday accused China of taking President Vladimir Putin's side in the Ukraine conflict as Beijing refuses to condemn Russia over the crisis.

"President Xi (Jinping) says he's being neutral in this conflict. There is no neutrality in this conflict," said Amy Gutmann, who was confirmed as the US ambassador under President Joe Biden last month after tumultuous years with Donald Trump's envoy.

"Not to denounce Mr Putin's aggression as aggression... is taking a side. China is taking Mr Putin's side in this conflict," Gutmann told journalists at the US embassy in Berlin.

Gutmann, 72, the daughter of a Holocaust survivor, was confirmed as the new ambassador to Germany by the US Senate in February.

The United States had previously been represented in Berlin by Trump ally Richard Grenell, who raised hackles in Germany with a combative approach, including vowing to empower anti-establishment right-wingers in Europe.

He regularly angered his host country with outspoken criticism of everything from the Iran nuclear deal to Berlin's defence spending and relations with Chinese tech firm Huawei.

The new US Ambassador to Germany Amy Gutmann: 'There is no neutrality in this conflict'
The new US Ambassador to Germany Amy Gutmann: 'There is no neutrality in this conflict' AFP / Stefanie LOOS

Gutmann was previously president of the University of Pennsylvania, an Ivy League institution, and is an expert in democratic processes.

She served as chair of Barack Obama's Commission for the Study of Bioethical Issues.

Gutmann said her Jewish father Kurt, who died when she was a teenager, "was and still is my model of courage".

"It's deeply ingrained in my consciousness and my psyche that I would not be alive today if it weren't for the fact that my father saw the handwriting on the wall," she said.

As a college student in 1934, Kurt had realised that he, his four siblings and his parents would not be safe in the country under Adolf Hitler and convinced them to flee to India.

He later settled in New York, where Gutmann was born.