As the U.S. Senate looked to a day of negotiating on health care legislation Thursday, President Donald Trump at 8:52 a.m. began unleashing tweets attacking the IQ, mental stability and physical appearance of MSNBC "Morning Joe" co-host Mika Brzezinski.

I heard poorly rated @Morning_Joe speaks badly of me (don't watch anymore). Then how come low I.Q. Crazy Mika, along with Psycho Joe, came.. — Donald J. Trump (@realDonaldTrump) June 29, 2017

...to Mar-a-Lago 3 nights in a row around New Year's Eve, and insisted on joining me. She was bleeding badly from a face-lift. I said no! — Donald J. Trump (@realDonaldTrump) June 29, 2017

White House deputy press secretary Sarah Huckabee Sanders defended the president's behavior in a Thursday afternoon press briefing, saying "the American people elected a fighter," and that's what they got.

But Republicans and Democrats criticized the president for his tweets -- shocking even for Mr. Trump's Twitter account -- as the Senate struggles to propose a passable bill on health care. Mr. Trump met Wednesday with senators earlier this week as he attempts to negotiate the bill, and Vice President Mike Pence on Thursday met one-on-one with senators on Capitol Hill.

The tweets also detracted from the White House's designated policy focus of the week -- energy -- and two bills expected to pass in the House Thursday to crack down on immigrants who commit crimes and attempt to re-enter the country illegally, and on "sanctuary cities" refusing to cooperate with federal immigration authorities. Mr. Trump made stricter stances on immigration -- a theme drowned out by his tweets Thursday -- a central message of his campaign.

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Both Republicans and Democrats criticized the president Thursday.

Sen. Lindsey Graham (R-South Carolina), who told CBS News' "Face the Nation" last month that the president is "his own worst enemy" with counterproductive tweets, said Mr. Trump behaved "beneath the office."

Mr. President, your tweet was beneath the office and represents what is wrong with American politics, not the greatness of America. — Lindsey Graham (@LindseyGrahamSC) June 29, 2017

Alaska GOP Sen. Lisa Murkowski told Mr. Trump to, "Stop it!"

Stop it! The Presidential platform should be used for more than bringing people down. — Sen. Lisa Murkowski (@lisamurkowski) June 29, 2017

@POTUS, do you want to be remembered for your tweets or your accomplishments? — Sen. Lisa Murkowski (@lisamurkowski) June 29, 2017

Rep. Lynn Jenkins, a Kansas Republican, said the president's Twitter outburst was, "not OK."

This is not okay. As a female in politics I am often criticized for my looks. We should be working to empower women. https://t.co/sV6WDE0EUD — Lynn Jenkins (@RepLynnJenkins) June 29, 2017

Rep. Carlos Curbelo (R-Florida) pointed out that the shooting at a congressional baseball practice -- after which Mr. Trump himself urged unity -- was just two weeks ago. House Majority Whip Steve Scalise (R-Louisiana) is still in the hospital after he was seriously injured by a shot to the hip.

Let's all remember the lessons from the Congressional shooting just a couple weeks ago. We must treat one another with decency & respect — Carlos Curbelo (@carloslcurbelo) June 29, 2017

Sen. Susan Collins (R-Maine) urged "respect" and "civility."

This has to stop – we all have a job – 3 branches of gov’t and media. We don’t have to get along, but we must show respect and civility. — Sen. Susan Collins (@SenatorCollins) June 29, 2017

Rep. Mike Coffman (R-Colorado) used the hashtag, "StopTheTwitterTantrums."

The President’s tweets are beneath the dignity of his office. It needs to stop. #StopTheTwitterTantrums — Rep. Mike Coffman (@RepMikeCoffman) June 29, 2017

Democrats were even more blunt.

House Minority Leader Nancy Pelosi (D-California) called Mr. Trump's tweets, "so blatantly sexist I don't even know that there's any question about it."

"I just don't know why the Republicans, they can tolerate almost anything: a candidate beating up a reporter and then cheering him on as he arrives in Congress, the tweets of the president of the United States," Pelosi added, referring to Montana Republican Rep. Greg Gianforte's assault on a reporter the night before he was elected to Congress.

Rep. Lois Frankel (D-Florida), in a press conference with more than two dozen Democratic members of Congress, called Mr. Trump the "cyber bully in chief."

"And once again, he is ... embarrassing our nation with what I call his bloody tweets," Frankel said.

Other Democrats pointed out that Mr. Trump is hurting legislative progress. Rep. Chellie Pingree (D-Maine), called the president's attacks on the media a "constant distraction."

.@RealDonaldTrump's attacks on media have sunk to a new low. This constant distraction is hurting the ability of Rs & Ds to get work done. — Chellie Pingree (@chelliepingree) June 29, 2017

Rep. David Cicilline (D-Rhode Island) asked anyone to tell him how the president's tweets help "create jobs" or "make health care better," issues Mr. Trump has said are among his top priorities.

If anyone can tell me how these sexist attacks are going to create jobs or make health care better, let me know. https://t.co/S6hBoknfBc — David Cicilline (@davidcicilline) June 29, 2017

Mr. Trump didn't stop criticizing the media Thursday. As the House and Senate wrapped up their legislative business before the July 4 holiday, Mr. Trump, at a Department of Energy event with Vice President Mike Pence and Secretary of Energy Rick Perry Thursday afternoon, repeated his frequent line that CNN is "fake news."