Leading consulting firm Eurasia Group says US division over the upcoming presidency of Joe Biden is the top political risk facing the world in 2021.
The US consultancy on Monday listed the top 10 risks it expects to play out during 2021.
It says Biden, who is scheduled to be sworn in on January 20, "will be seen as illegitimate by roughly half" the United States.
The group says that is as long as incumbent President Donald Trump and his supporters continue to refuse to accept the results from November's presidential election, saying it was "stolen."
Eurasia Group says that facing intensified opposition from Republicans in Congress, "Biden will find it more difficult to govern than under the 'normal' conditions of split government."
It adds that such domestic polarization "means the US won't inspire as much new confidence as Biden hopes" in the international community.
The group chose "Long COVID" as the second-highest risk. It warns that "neither the coronavirus nor its wide-ranging impacts will disappear," even after widespread vaccination begins, and that the spread of infection may widen wealth gaps in many countries.
It adds that there could also be a gap between developed and developing countries in terms of access to COVID-19 vaccines.
The group chose broadening tensions between the US and China as its No.4 risk.
It says that China is poised to outperform the US in "vaccine diplomacy," spreading its influence in regions such as Southeast Asia and Latin America. It also expects rivalry over green technologies to be a source of friction.