New York (CNN Business) President Trump's 2020 campaign announced Monday that it will no longer credential Bloomberg News reporters for its events after the outlet said it would not conduct investigations into the Democratic presidential candidates, but would continue to probe the Trump administration.

"The decision by Bloomberg News to formalize preferential reporting policies is troubling and wrong," Brad Parscale, Trump's 2020 campaign manager, said in a statement.

Bloomberg News announced last month that it would not investigate the Democratic presidential candidates after its owner, Mike Bloomberg, jumped into the race for the 2020 Democratic presidential nomination.

The outlet has long avoided probing its owner and said it would continue to do so as he seeks the nomination. To level the playing field, Bloomberg News said it would also not investigate the other Democratic presidential candidates.

But, the outlet said it would continue to investigate the Trump administration "as the government of the day." That decision prompted the protest from the Trump campaign on Monday.

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