President Donald Trump reportedly wants to take on Amazon and the internet retail behemoth's tax treatment.

It is unclear what the president would, or could, do on his own, but actions in the two other branches of government could settle the issue for him.

The president has long argued that Amazon gets unfair tax treatment relative to brick-and-mortar retailers. Trump is "obsessed" with Amazon and wants to "go after" the company, Axios reported on Wednesday, citing sources. The company's stock, in turn, lost more than $50 billion in shareholder value at one point Wednesday.

Amazon shares flagged Thursday, too, after Trump tweeted more criticism about the online retailer. "Unlike others, they pay little or no taxes to state & local governments," the president wrote.

On Wednesday, White House press secretary Sarah Huckabee Sanders denied that the White House planned any imminent move against Amazon. "We have no announcement and no specific policies we are pushing for" related to Amazon, she said.

The president's reported stance on the company isn't new. In several tweets in recent years, Trump has argued for changes in how Amazon purchases get taxed. At issue is whether a state sales tax is levied on purchases made from a third-party Amazon vendor.

Trump tweet

Last year, the online retailer started to collect sales taxes on products it sells directly to consumers in states that levy such taxes. But some retail competitors argue the policy for third-party vendors gives Amazon an unfair advantage.