The United Auto Workers chief on Wednesday blasted Ford's decision to send production of electric vehicles to Mexico, out of its home base in Michigan.

UAW President Dennis Williams also complained that the massive tax bill approved by Congress on Wednesday failed to provide funding to key investments to make the US more competitive.

"I'm not happy with Ford," Williams told reporters at the union's headquarters. "I think we're missing a huge opportunity in this country."

Ford announced earlier this month that it planned to shift production of electric vehicles to Mexico, reversing a previous decision to produce the cars at its Flat Rock, Michigan plant.

The company said the decision allows it to make room at Flat Rock to manufacture self-driving cars. It will boost the intended investment there to $900 million, creating 850 jobs, according to press reports.