New Mexico Sen. Martin Heinrich (D) accused Attorney General Jeff Sessions of obstructing Congress' probe into President Trump and Russia.

Heinrich became irritated when Sessions said it "would not be appropriate" to discuss private conversations between himself and Trump.

Sessions said that while he doesn't have the right to claim executive privilege and not respond to such questions, Trump does.

"Because you're invoking executive privilege," Heinrich said. He reminded Sessions that he swore an oath to "tell the whole truth."

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"And now, you're not answering questions. You're impeding this investigation," Heinrich said.

Heinrich told Sessions he could either answer his question, or promise to answer in closed (non-public) Senate session.

"There is no 'appropriate'-ness bucket," Heinrich said.

Sessions said that Justice Department's rules allow him to decide what may or may not be appropriate to discuss publicly.

"I'm protecting the president's constitutional right by not giving it away before he has a chance to [do so]," Sessions said.

"You are obstructing [a] Congressional investigation," Heinrich said.

Later Tuesday, Heinrich told CNN that Sessions should be expected to answer all questions.

"This is not a backyard barbecue," he said.

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