The two Democratic commissioners at the U.S. Federal Trade Commission said they were illegally fired by President Donald Trump on Tuesday, in another major test of the independence of regulatory agencies.
The White House did not immediately respond to a request for comment.
Commissioners Alvaro Bedoya and Rebecca Kelly Slaughter released separate statements saying they had been fired from the consumer protection agency.
Trump has already sparked lawsuits by firing members of other independent agencies including the National Labor Relations Board.
The U.S. Supreme Court ruled in 1935 to uphold a law that allows FTC commissioners to be fired only for good cause, such as neglecting their duties.
The ruling shields a number of independent, bipartisan multi-member agencies from direct control by the White House.