The White House on Thursday said President Donald Trump would not accept an "incredible offer" from Russian President Vladimir Putin.

During the Helsinki summit between the two leaders on Monday, Putin offered to permit U.S. investigators to interrogate Russians charged with hacking during the 2016 election, in exchange for the United States agreeing to allow the Kremlin to interrogate U.S. citizens about unspecified crimes.

“It is a proposal that was made in sincerity by President Putin, but President Trump disagrees with it," White House Press Secretary Sarah Sanders said in a statement Thursday. "Hopefully President Putin will have the 12 identified Russians come to the United States to prove their innocence or guilt."

The statement, coming three days after Trump's initial comment, was the latest example of back tracking the White House press office has undertaken since Trump's stunning joint press conference with Putin on Monday. There Trump called Putin's proposal an "incredible offer." Trump also signaled that he believed Putin's denial that Russia meddled in the 2016 presidential election and cast doubt on his own intelligence services' assessment that Russia did, in fact, interfere.

"I have great confidence in my intelligence people, but I will tell you that President Putin was extremely strong and powerful in his denial today, and what he did is an incredible offer," Trump said in Helsinki, Finland. "He offered to have the people working on the case come [to Russia] and work with their investigators with respect to the 12 people. I think that’s an incredible offer."

Initially, that statement did not get the kind of bipartisan backlash that Trump's comments about his intelligence services received. But on Wednesday when asked about it, rather than dismiss Putin's offer out of hand, Sanders said the president would "work with his team" to assess it.

A wide range of observers were outraged that the American president would even consider permitting Russia to question U.S. officials, including former U.S. ambassador to Russia Michael McFaul, for alleged crimes relating to tax evasion by British financier Bill Browder.

The White House announced Trump’s rejection just before the Senate's unanimous vote to approve a resolution telling the president not to accept Putin’s request.

"He said it was an interesting idea. He didn't commit with anything," said Sanders. "He wants to work with his team and determine if there's any validity that would be helpful to the process. But again, we've committed to nothing. And it was an idea that they threw out."