Anthony Gardner, who represented the Obama administration as ambassador to the EU, says that world leaders should help Mr Biden achieve a real victory against China.
This, he claims, would help nullify the one-term president’s attacks on Mr Biden and reduce the chance of Mr Trump returning to power in 2024.
“There’s always that risk, that’s what democracies are about,” Mr Gardner told Politico’s Playbook.
“That’s exactly why you in Europe should think about how you can contribute to the success of the administration.”
Mr Gardner, who held the ambassadorship between 2014 and 2017, says that leading nations should work together on trade to take on China.
“We cannot afford to go through the motions,” he added.
“We need to make clear to our electorate and our voters that working multilaterally, with rules and institutions, yields better results, and that communiques are no substitute for results
“Some Europeans won’t like it to be put this way. But this is the acid test. This is the reality today. What good is Europe if it’s not going to work with us on this issue?”
Mr Trump, who claimed during the 2020 campaign that his opponent was soft on China, has not formally confirmed he will run for the Republican nomination for president in 2024, but has hinted at it and been strongly tipped to do so.
Observers say that Mr Biden has largely carried on his predecessor’s policy towards Chinese tech and other companies, recently expanding a ban on US investment in companies it believes are linked to the Chinese military.
The order goes into action on 2 August, and includes companies such as smartphone maker Huawei and Hikvision, a manufacturer of video surveillance equipment.
Although Mr Biden has taken a more diplomatic tone towards China, tensions still exist, as evidenced by a March summit in Alaska that turned into a diplomatic spat.
In March, Mr Biden’s State Department also declared China’s treatment of Uyghur Muslims in Xinjiang a genocide.