(CNN) A lawyer for the Ukraine whistleblower, whose complaint document triggered the House impeachment inquiry of President Donald Trump, has sent a letter to the White House warning the President to "cease and desist" attacking his client.

"I am writing out of deep concern that your client, the President of the United States, is engaging in rhetoric and activity that places my client, the Intelligence Community Whistleblower, and their family in physical danger," Andrew Bakaj wrote to White House counsel Pat Cipollone in a Thursday letter obtained by CNN's Anderson Cooper.

"I am writing to respectfully request that you counsel your client on the legal and ethical peril in which he is placing himself should anyone be physically harmed as a result of his, or his surrogates', behavior," he said.

Trump has repeatedly attacked the whistleblower and tried to discredit the individual, saying he, Trump, deserves to "meet his accuser" and has demanded the whistleblower's identity be revealed. The President has also accused the whistleblower of partisanship though Trump said he had no personal knowledge of the person's identity.

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