Tesla Inc. Chief Executive Officer Elon Musk challenged the United Auto Workers union to hold a vote at its California factory, after President Joe Biden once again avoided mentioning the world’s most valuable electric carmaker while promoting EVs in his State of the Union speech on March 1.

“I’d like hereby to invite UAW to hold a union vote at their convenience,” Musk wrote in a tweet early March 3. “Tesla will do nothing to stop them.”

Our real challenge is Bay Area has negative unemployment, so if we don’t treat and compensate our (awesome) people well, they have many other offers and will just leave!

I’d like hereby to invite UAW to hold a union vote at their convenience. Tesla will do nothing to stop them.

— Elon Musk (@elonmusk) March 3, 2022

Musk, the world’s richest person according to the Bloomberg Billionaires Index, said that Tesla’s biggest challenge in the Bay Area was fierce competition for talent, which requires the company to compensate and treat its employees well. He claimed that Tesla workers receive the auto industry’s highest compensation even without unionization.

The Tesla CEO was responding to a tweet by Gene Simmons, the co-lead singer of rock band KISS, who criticized Biden for not mentioning the company. “Give Elon Musk/Tesla its due,” Simmons said. “They are game changers and should be heralded.”

Biden, a top labor union ally, has frequently snubbed Tesla in favor of General Motors Co. and Ford Motor Co., whose progress on electric vehicles he’s frequently touted despite far smaller sales of such cars. Musk has previously expressed unsympathetic views toward labor unions, from whom Biden has long drawn support.