Former Vice President Joe Biden said Thursday that Trump should be ready and able to answer questions about the probe into Russian election meddling, after he said Wednesday that he would advise Trump not to be interviewed by special counsel Robert Mueller if he were Trump's lawyer.

"A president should be prepared to answer the questions about one of the most serious security breaches that’s occurred in American history, Russia attempting to affect and impact on the American electoral process," Biden told MSNBC.

"I can’t fathom why the president, just as a patriotic American let alone as president, would not be looking for every single bit of data and evidence that would show what [Russia was] doing and what [it is] attempting to – continue to attempt to do," he continued.

But Biden said it could have implications for Trump because "he does not tell the truth, he is not accurate in much of what he says."

Biden also said it's "long past due" that White House staff secretary Rob Porter, who has been accused of domestic violence by two of his ex-wives, leave his job.

"The culture’s changing, thank God, but not fast enough," Biden said. "And the idea that this would happen in the Oval Office ..."

When asked about reports Trump did not know one of his top advisers did not have clearance, Biden said the perception of "controlled chaos" within the Trump administration was hurting the country's reputation at home and abroad.

"I’m having enormous difficulty understanding how this White House functions and who’s on first, who’s on second, and who’s pitching, who’s catching? I mean, it really is confusing," he said.