The attorneys general of Maryland and Washington, D.C., plan to file a "major lawsuit" against President Donald Trump as early as Monday, they said Sunday night.

Maryland Attorney General Brian Frosh and his D.C. counterpart, Karl Racine, didn't disclose the focus of the litigation, which they said in a statement they would formally announce Monday afternoon.

President Donald Trump signs executive orders at the Pentagon on Jan. 27. Olivier Douliery / EPA File

The Washington Post reported that the lawsuit would allege that Trump has violated constitutional anti-corruption restrictions by accepting payments and benefits from foreign governments since he became president.

No further details were immediately available.

The lawsuit would be the first related to Trump's business interests brought by government entities. Citizens for Responsibility and Ethics in Washington, a nonprofit activist group, has separately sued Trump in U.S. District Court in Manhattan alleging "countless conflicts of interest" in violation of the Constitution's so-called emoluments clause.

In January, Trump promised to track and donate all profits from foreign government travel and commerce at his companies to the U.S. Treasury. But NBC News and MSNBC reported last month that the Trump Organization hasn't been tracking all possible payments it receives from foreign governments.

Company policy detailed in a new pamphlet suggests that it is up to foreign governments, not Trump's hotels, to determine whether foreign governments self-report their business dealings.

"To attempt to individually track and distinctly attribute certain business-related costs as specifically identifiable to a particular customer group is not practical," the pamphlet states.