The US is considering 25% tariffs on $200bn (£152bn) of Chinese goods, much higher than the 10% it previously indicated it might impose, reports say.
The plan could be announced as early as Wednesday but the higher figure has not been finalised, sources told US media.
It would risk further escalating tensions between the US and China which are already mired in a trade war.
The US in July published a list of $200bn worth of additional products to be taxed as early as September.
The list named more than 6,000 items including chemicals, textiles, minerals and consumer goods ranging from baseball gloves to frozen fish fillets.
The US opened fire in a trade war with 25% tariffs on $34bn of Chinese goods, and China retaliated in kind.
US threats have escalated since, with US President Donald Trump saying he is ready to slap tariffs on all $500bn of Chinese imports.
The US accuses China of intellectual copyright theft and wants to bring down its lofty trade deficit with the world's second largest economy.
But the trade dispute is also seen as part of a broader tug of war between the two powerhouses for influence on the world stage.
On Monday US Secretary of State Mike Pompeo announced a plan to spend $113m in Asia, a move that was widely seen as an attempt to counter China's growing influence in the region.
Bloomberg, which was the first to report the news of the higher tariffs, also said US and Chinese officials were having private conversations as they sought to resume negotiations.
The US is also expected to soon announce tariffs on the remaining $16bn of the $50bn of Chinese goods the US originally planned to tax.
A public hearing on the second round of tariffs took place last week and the USTR has a 31 July deadline for post-hearing comments.