'Deeply misguided' to wall US off with tariffs: Yellen

US Treasury Secretary Janet Yellen will push back Thursday on Republican presidential candidate Donald Trump's proposals of high tariffs on allies and rivals, calling such moves "deeply misguided" weeks before the November 5 election.

Her prepared remarks, to be delivered in New York, come as Trump vows to impose across-the-board levies on US imports, with a particularly high tariff level on Chinese goods.

The former president is running against Democrat Kamala Harris, whose term in President Joe Biden's administration has seen more targeted economic policies against countries like China.

"Calls for walling America off with high tariffs on friends and competitors alike or by treating even our closest allies as transactional partners are deeply misguided," Yellen says in the speech to be delivered at the Council on Foreign Relations.

Trump has called for a 10% to 20% tariff on all imports and a higher rate of 60% on those from China.

But Yellen warns that sweeping levies would raise costs for US households and make American businesses less competitive.

The economy has consistently been a top issue for voters, according to polls leading up to the November 5 election.

"And we cannot even hope to advance our economic and security interests, such as opposing Russia's illegal invasion of Ukraine if we go it alone," Yellen adds.

But the Treasury chief acknowledges that the United States also "cannot simply draw from an old playbook" when facing challenges like global pandemic preparedness, climate change and a need to grapple with China's industrial overcapacity.

She notes that trade and investment with China can bring gains to US firms and workers, stressing that Washington should aim to have "a healthy economic relationship based on a level playing field."