On Tuesday, President Donald Trump tweeted an apparent response to Michael Flynn's resignation as national security adviser, commenting on "so many illegal leaks coming out of Washington."

A number of lawmakers, including Chairman of the Senate Homeland Security Committee Sen. Ron Johnson (R-WI), have questioned how the conversations Flynn had with Russian Ambassador Sergey Kislyak leaked to the media.

According to The Washington Post, current and former U.S. officials said Flynn privately discussed U.S. sanctions against Russia before Trump's inauguration. After initially denying talks of sanctions, Flynn "indicated that while he had no recollection of discussing sanctions, he couldn't be certain that the topic never came up," his spokesman said last week.

Johnson was a guest earlier on "America's Newsroom" to discuss his concerns over the leaks.

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"I want to see this president succeed. There are so many challenges America faces, we have to have a president that can actually succeed," said Johnson, adding it's an "enormous challenge" for Trump as he faces "entrenched bureaucracy" within the intelligence community, State Department and throughout the government.

Johnson said the questions about who tapped the phones, who listened in to the conversations and who leaked the information must be asked, adding these questions must be asked in a classified setting.

"Leaks of this nature are incredibly damaging to America, to our national security, and we need to look into it," Johnson said.

He said Flynn's conversations should have never been leaked in the first place and should not be in the public domain right now.

Watch the full interview above, and share your thoughts with us in the comments section.

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