The US Justice Department will "announce a major, international cryptocurrency enforcement action" on Wednesday, it said in a statement, adding the US Treasury Department will also make an announcement.
"The US Department of the Treasury will also announce an action in this space," the statement said.
US officials, including Deputy US Attorney General Lisa Monaco and Deputy US Treasury Secretary Wally Adeyemo, will deliver remarks at 12 p.m. (1700 GMT) in Washington, according to the statement.
Other officials will include the associate deputy director of the FBI and the US attorney for the Eastern District of New York.
Representatives for Treasury declined to comment further.