(CNN) For almost two-and-a-half hours Thursday, Democratic members of Congress implored a federal judge to give them more ability to stop President Donald Trump's family businesses from accepting payments from foreign governments.

The case, before US District Judge Emmet Sullivan in Washington, DC, challenges how the Trump Organization has received trademark approvals from China, hotel rentals and real estate purchases from Saudi Arabian, Emirati and other foreign interests and favorable regulatory decisions from foreign governments while Trump serves in the White House. Congress should learn details about the transactions -- called emoluments in this case, a term outlined in in the US Constitution — and approve them before Trump Organization can accept them, the members of Congress allege.

"The reason the founders put that provision in the US Constitution was to ensure that the President of the United States put the nation's interests ahead of his own," Sen. Richard Blumenthal, a lead plaintiff on the suit who was in court Thursday, said afterward.

"This provision (on emoluments) involves more than just corruption," Blumenthal added. "It involves our national security. The stakes could not be higher."

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