The US president wants the final communique to condemn forced labour in Xinjiang, where more than one million Muslims have been detained in a vast system of camps, officials said.
However, there was said to be a “spectrum of how far different countries are willing to go” in their criticism – amid suggestions the UK will side with the US as a fellow hawk.
Canada and France are also largely endorsing Mr Biden’s stance, a US source said, while Germany, Italy and the EU leadership were more hesitant at a summit discussion.
The potential clash emerged as the G7 was expected to agree an infrastructure plan for poorer countries as a counter to the growing influence of China, funding railways in Africa and wind farms in Asia for example.
China has stolen a march with its 2013 Belt and Road Initiative, which has seen more than 100 countries sign agreements to cooperate in railways, ports, highways and other infrastructure projects.
It is seen as a vehicle for Communist China to expand its influence – an accusation Beijing dismisses as an “imperial hangover” from the days of Western humiliation of its country.
The White House made clear its intentions, a senior official telling Reuters: “Until now we haven’t offered a positive alternative that reflects our values, our standards and our way of doing business.”
The UK government was criticised last week for failing to take action to prevent companies sourcing goods made by Uighur forced labour in Xinjiang.
It rejected proposals put forward by the Commons business committee to strengthen procurement rules, after personal protective equipment was bought from firms facing modern slavery allegations.
The US president is pushing for a united front, as the G7 seeks to compete economically with Beijing, but some EU countries are keener to maintain commercial links.
China has denied all accusations of forced labour or abuse, first denying the camps existed before insisting they are vocational centres designed to combat extremism.
But UN experts and rights groups estimate over a million people, mainly Uighurs and other Muslim minorities, have been detained.
The Chinese Embassy in the UK hit out at its targeting at the summit, saying: “The days when global decisions were dictated by a small group of countries are long gone.
“There is only one system and one order in the world, that is, the international system with the UN at the core and the international order based on international law.”