London: On the second day of the Group of Seven (G7) summit, world leaders expressed serious differences over how best to approach China, according to a senior official of US President Joe Biden's administration.

The disagreements at the tense session reportedly became so sensitive that all internet was shut off to the room. The arguments pitted European nations against the United States, Britain and Canada, who urged for stronger action against China for its authoritarian practices, including forced labour practices in Xinjiang province, CNN reported.

Where officials did agree was on establishing an infrastructure initiative to compete with China's Belt and Road Initiative (BRI), by announcing the 'Build Back Better World' (B3W) partnership that will address the infrastructure needs of low and middle-income countries.

Officials described the China issue as one of the most challenging elements of the G7 gathering.

"There was some interesting discussion, and a little bit of differentiation of opinion on, not whether this threat is there but on how strong, from an action perspective, I think different G7 members are willing to take things," the official said.

At one point, Biden made a forceful call to other leaders about vocally calling out China's anti-democratic practices, emphasising the need to take action, informed an official.

Biden was joined by British Prime Minister Boris Johnson, Canadian Prime Minister Justin Trudeau and French President Emmanuel Macron on pushing for tougher action on China.

However, German Chancellor Angela Merkel, Italian Prime Minister Mario Draghi and leaders from the European Union sought to emphasise areas of cooperation with China, reported CNN.

CNN reported that the session, despite differences, was marked by new respect among the leaders after four years of tension under former US President Donald Trump.

"These leaders really seem to like each other and respect each other, and work through where that sweet spot might be," the senior administration official said.

The G7 summit began formally on Friday as the leaders of the world's most advanced economies gathered on the Cornish coast for the first time since the outbreak of global coronavirus pandemic. The gathered nations will pledge to donate 1 billion COVID vaccine doses, with the US providing about half of those shots.