File Photo: Lawyer John Dowd exits Manhattan Federal Court in New York, U.S. on May 11, 2011. (Xinhua/REUTERS)

WASHINGTON, March 22 (Xinhua) -- John Dowd, U.S. President Donald Trump's lead lawyer who was handling the response to the special counsel investigation into alleged collusion between the Trump campaign and Russia meddling in the 2016 presidential election, resigned on Thursday.

Dowd had considered leaving several times in recent months and concluded that Trump was increasingly ignoring his advice, according to The New York Times.

Trump's lawyers, under the leadership of Dowd since last summer, had advised the president to cooperate with special counsel Robert Mueller, who is also looking into whether Trump obstructed the inquiry.

File Photo: U.S. President Donald Trump speaks in a national address regarding the mass shooting in Parkland, Florida, at the White House in Washington D.C., the United States, on Feb. 15, 2018. (Xinhua/Ting Shen)

Dowd's departure comes after Trump began publicly attacking Mueller and his team. In a tweet last weekend, Trump said that the Mueller probe "should never been started."

Following Trump's remarks, Dowd called for an end to the investigation. He originally claimed to be speaking on Trump's behalf but backtracked later by saying that he was only speaking for himself.

Trump's lawyers are also in the midst of negotiations with the special counsel's team over a potential interview involving the president.

On Thursday, Trump said that he's still willing to talk to Mueller, an idea that Dowd has reportedly opposed to.

Dowd is also leaving three days after Joseph diGenova, a former federal prosecutor, was added to the Trump' s legal team for Mueller's probe.

DiGenova, in an interview with Fox News two months ago, alleged that FBI officials were involved in a "brazen plot" to exonerate Hillary Clinton in the email investigation and to "frame" Trump for nonexistent crimes.