Joe Biden has seized on claims made in John Bolton’s explosive book regarding Donald Trump’s relationship with China.

Bolton - Trump’s former national security adviser - alleges the President urged China's Xi Ji-nping to help him win re-election, a revelation which could undermine his campaign's effort to portray Democratic rival Biden as soft on Beijing.

Biden's top aides moved quickly on Thursday to argue that it's Trump who has taken a weak approach to the rising superpower. They seized on accusations from Bolton that the president continually kowtowed to Xi and ignored human rights abuses while trying to get his foreign counterpart’s assistance with domestic politics.

“The Bolton allegations are just the most noxious and hateful cherry on top of a sundae that already existed here," Ron Klain, a longtime Biden adviser, said in an interview. 

"We have seen for three years that Donald Trump has curried favor with authoritarian regimes that are willing to help him personally and politically.”

China already loomed large in the contest as Trump and Biden have traded accusations over corruption, geopolitical pandering and the president’s shifts in tone toward the country during the coronavirus pandemic, which ignited in the central Chinese city of Wuhan. But Bolton's accusations intensified the debate with less than five months remaining until the election.

Biden's team hopes the book will help reinforce their argument that the administration was slow to react to the pandemic, in part because of the tone set by Trump.

Trump’s team insists the president has taken a strong stance against Beijing.

“President Trump is the first president to actually stand up to China for their decades of trade cheating and he has held them accountable for lying to the world about the coronavirus,” said Tim Murtaugh, the Trump campaign’s communications director.

 “Joe Biden has spent his entire career appeasing China, failing to take them seriously as an economic competitor, and allowing his son Hunter to profit wildly through a Chinese-controlled bank.”

Democrats hope to keep the pressure on Trump into the autumn. The Democratic National Committee this week launched a six-figure digital and television ad campaign hitting Trump on China, which party officials say will expand in the coming weeks. 

And it allows the Biden campaign to return to an issue that aides see as one of the candidate’s key assets in the campaign: his foreign policy experience and pledge to restore America’s standing as a global leader.

But Trump's allies have no plans to cede the matter. Beyond the pandemic, they still believe they can link the Obama administration's trade deals and economic policy to the loss of manufacturing jobs, particularly in the vital battlegrounds of Pennsylvania, Michigan, Ohio and Wisconsin, a strategy that worked in 2016.

“The upper Midwest was in a decline and it's because those jobs are in China and we won with that," said Steve Bannon, the chief executive officer of Trump's 2016 campaign, in a recent interview. 

“Trump can still deliver a tough message about getting those jobs back. Biden is the wrong guy for the moment," he said.