New York (CNN Business) Joe Biden's presidential campaign says President Donald Trump's personal attorney Rudy Giuliani does not belong on TV.

Why? Because he spreads "unhinged, unfounded and desperate lies" through his TV interviews.

In a highly unusual letter to the major networks — including CNN — on Sunday, the Biden campaign said booking Giuliani does a disservice to viewers.

The letter from Biden officials Anita Dunn and Kate Bedingfield says "we ask that you no longer book him on your air." Barring that, the Biden campaign wants "an equivalent amount of time" to be provided "to a surrogate for the Biden campaign."

It was sent to the moderators of the Sunday shows, their executive producers, and the heads of their respective news divisions. Those networks had no immediate comment on Sunday afternoon. CBS and CNN declined to comment.

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