The Biden administration has been asked to investigate four Chinese firms that are allegedly involved in Ford Motors’ planned battery plant in Michigan, according to a letter seen by Reuters.

The request has come from the chairs of two US House committees, Mike Gallagher, Chairman of the Select Committee on China and Cathy McMorris Rodgers, who chairs the Energy and Commerce Committee.

Ford’s partnership with CATL, first announced in February 2023, has drawn a backlash over security concerns and allegations of human rights abuses against Uyghurs and other ethnic minorities in the Xinjiang region.

Last July, a letter sent to Ford CEO Jim Farley by Mr Gallagher, alongside Jason Smith, Chair of the Committee on Ways and Means outlined “troubling” connections between CATL and the Chinese Communist Party (CCP).

The letter also alleged that the proposed partnership would give “well-paying jobs to citizens of the People’s Republic of China,” instead of American citizens.

In September 2023 Ford announced it had paused the development of its $3.5 billion plant in Marshall, Michigan. Lawmakers threatened to call Ford CEO Mr Farley to testify before Congress.

In the December of the same year, CATL hit back at accusations that its batteries posed an espionage threat, saying the accusations were “false” and “misleading.”

The Chinese firms named in the most recent letter have not been named, due to the confidential records that Ford’s CEO turned over.

In a statement made earlier this week, Ford said it follows "all government regulations across our business,” adding:

'Ford suppliers are required to meet our higher standards, including for protecting human rights, and obligated to extend those requirements to suppliers with whom they might work.'