Sen. Joe Manchin, West Virginia’s moderate Democrat in the upper chamber, on Tuesday threw cold water on any idea of his party adding a carbon tax to the $3.5 trillion reconciliation package they are working on passing.

The carbon tax talk began to heat up recently when Manchin’s fellow Democratic moderate, Sen. Kyrsten Sinema of Arizona, indicated in an interview that she might be favorable to the plan, The Hill reported Monday.

Sinema told The Arizona Republic that global warming is a factor in Arizona. But Manchin, whose state is a huge coal producer, wasn’t so warm to the plan. With an evenly split Senate, Democrats need his vote.

“I just heard about that,” Manchin told reporters Monday when asked about the issue. “Any type of a tax is going to be passed on to the people.”

“Now if a tax is going to be beneficial to help something and give us more research and development and innovation and technology, it’s something to look at,” he added.

Manchin said, however, that the carbon tax does not fall under that category, at least as it has been explained to him.

Sinema told the Republic last week: “We know that a changing climate costs Arizonans. And right now, we have the opportunity to pass smart policies to address it — looking forward to that.”

But The Hill quoted a Democratic aide as saying that Sinema “is not pushing or proposing a carbon tax.”