- Castro said the meeting should have been disclosed to the American people
- He wants to get a readout of the meeting from the White House
A senior White House official told CNN the discussion -- which was not disclosed at the time -- lasted "nearly an hour."
"That kind of meeting is not normal," Castro, a Texas Democrat, told CNN's Erin Burnett on "OutFront." "This is after they had reportedly a two-hour meeting earlier in the day, and so now to have a meeting for another hour where nobody else is present, not even an American translator, and not disclose what they talked about -- what kind of deals that may have made, what may have been offered in terms of foreign policy or otherwise -- to not share that with the American people is unacceptable. And so this can't be accepted as the new normal in terms of how the president conducts himself or herself with leaders of foreign countries."
Castro, who is a member of the Senate intelligence and foreign affairs committees, said "we certainly intend" to ask for a full readout of the meeting from the White House.
"We want to know exactly what was discussed," he said, adding that he wants to know whether the Russian translator who was there for the discussion took any notes of the meeting.
The White House, in a statement Tuesday night, sought to downplay the significance of the discussion.
"It is not merely perfectly normal, it is part of a president's duties, to interact with world leaders," the statement said.
The statement also disputed characterizing the discussion as a "second meeting," but instead called it a "brief conversation."