It could still be several weeks before a nominee is announced, analysts added. Hobbled by poor cooperation with the departing Trump administration during the transition, the Biden team is scrambling to get bodies into seats.

Biden was unable to have a single cabinet member confirmed before his inauguration on January 20; for comparison, Trump had two by that time, Barack Obama had six, George W. Bush had seven and Bill Clinton had three. The Senate only voted to confirm Linda Thomas-Greenfield as US ambassador to the United Nations on Tuesday, a month after her nomination hearings.

Linda Thomas-Greenfield headed to crisis-plagued UN as China challenges loom

Former diplomats note that four years of increasingly strained relations have narrowed the scope of the job, opportunity for creativity and even chances to meet senior Chinese officials.

“The conduct of relations with China is a very scripted affair, with few opportunities for foreign diplomats to represent their country on their own terms,” said Rocafort. “For persons with experience in more open societies, this could be frustrating.”

Frequently, top ambassador spots in the US political system are handed out as gifts to major political donors or to prominent domestic politicians. This often makes a close relationship with the president at least as important as foreign policy expertise in the region.

For example, Clark Randt, Bush’s choice for China, had been a major contributor to Republican candidates and the president’s fraternity brother at Yale University in the late 1960s.

The Biden administration could signal a shift from past practice, however, by selecting a top-level career professional or military leader for the job, analysts said. Not only would this mark a sharp break with the policies of the Trump administration, it would also underscore the gravity of the “China challenge”.

“That kind of choice would signal that the relationship is about practical, interest-based policies and not political appearances,” said Kevin Nealer, a former member of Obama’s Intelligence Advisory Board.

Analysts said that the next ambassador will carry out – but probably not shape – Washington’s response to Beijing’s more muscular policies as it squeezes Hong Kong and Xinjiang and pushes boundaries in the South China Sea and along the de facto border with India.

“US-China relations have been redefined not just by Trump, but more so by Xi Jinping – the ‘X’ factor in bilateral relations now,” said Nealer, now with the Scowcroft Group.

The Chinese leader’s “risk-indifference and willingness to break Chinese ‘hide and bide’ conventions and roll back reforms makes Embassy Beijing a very different job than at any time in the recent past”, Nealer added.

No matter who Biden selects, China will interpret the appointment as a mark of respect, said Jorge Guajardo, a former Mexican ambassador to China and now senior director with McLarty Associates.

“In terms of Mexican ambassadors, China is not even in the top 10, behind the United States, Spain, many others,” he said. “But I remember every time I’d approach someone in China they’d say ‘Oh you must be very powerful to be named ambassador to China’.”

“They always assume ambassador to China has to be the most important person named from that country, that President Biden is spending sleepless nights worrying about it.”

According to one China watcher in Washington who asked not to be identified given the sensitivity of personnel issues, the Biden administration hopes to limit naming political appointees as ambassadors to a quarter of the 170 or so heads of mission. That is less than the roughly 43 per cent that both Trump and Bush named and the 30 per cent under Obama.

Burns is said to be a front runner. Born in New York and raised in Massachusetts, he speaks French, Arabic and Greek. And despite his heavy focus on the Middle East and Russia, the long-time diplomat is seen as a safe and steady pair of hands. Since retiring from the United States Foreign Service in 2008, he has taught international relations at Harvard and consulted with the Cohen Group.

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China calls for dialogue with the US to restore ‘deteriorating relations’

China calls for dialogue with the US to restore ‘deteriorating relations’

“Burns seems like the most logical and likely choice, bringing diplomatic stature and an understanding of the complexity of the relationship – but also of the limitations of the role,” Michael Hirson, Asia head with the Eurasia Group and a former US financial attaché to China, said in a report.

“The key decisions on China will be made in Washington, and an effective ambassador’s most important task is likely to be informing that debate with on-the-ground observations.”

Another name receiving attention is Emanuel, who would likely bring a more confrontational approach to the job. Known as a sharp-tongued political street fighter, Emanuel has earned the nickname “Rahmbo,” a reputation amplified after he sent a dead fish to a political pollster who was late with his projections.

The Chicago native started out doing public interest work before moving into campaign organising and fundraising, eventually joining the Clinton administration and the Obama team.

Emanuel’s possible nomination has drawn criticism from progressive Democrats, who decry many of his actions while mayor of Chicago. In particular, they contend he ordered that footage of a police shooting of a 17-year-old African-American, Laquan McDonald, be suppressed for nearly a year. Emanuel has denied any cover-up.

“I would be a little surprised if Emanuel were chosen for China given his reputation for abrasiveness, but some in [Washington] may think that is exactly what we need at this time,” said Russell Menyhart, a former diplomat and now a lawyer handling international issues.

“What is most interesting is that you aren’t hearing rumours of anyone with a deep China background for the position. It shows how hard it is to identify someone with that background and yet sufficient stature in DC to be seen as qualified.”

Supporters have also called on Biden to name a woman or person of colour to the job, in keeping with his pledge to make his administration more representative. If named and confirmed, McCaskill, a Missouri senator from 2007 to 2019, would be the first female US ambassador to China.

Concerning the administration’s priorities, the Washington China watcher noted, “it’s impossible to exaggerate the instinct to diversity”.