Updated 1:30 p.m. | Rep. Joseph Crowley said Thursday he would not run against Alexandria Ocasio-Cortez, who defeated the New York Democrat in a primary last month. Ocasio-Cortez had accused him on Twitter earlier in the day of waging a third-party campaign against her.

.@repjoecrowley stated on live TV that he would absolutely support my candidacy.

Instead, he’s stood me up for all 3 scheduled concession calls. Now, he’s mounting a 3rd party challenge against me and the Democratic Party- and against the will of @NYWFP.https://t.co/Xvb6Jk8N8q — Alexandria Ocasio-Cortez (@Ocasio2018) July 12, 2018

While Crowley lost the Democratic nomination last month, he won the Working Families Party primary. (New York’s election system allows candidates to compete on multiple party lines.) So he will be on the November ballot for the 14th District, which includes parts of Queens and the Bronx.

But Crowley said he will not be actively campaigning. 

“Alexandria, the race is over and Democrats need to come together,” he tweeted in response to Ocasio-Cortez on Thursday. “I’ve made my support for you clear and the fact that I’m not running.”

Alexandria, the race is over and Democrats need to come together. I’ve made my support for you clear and the fact that I’m not running. We’ve scheduled phone calls and your team has not followed through. I’d like to connect but I’m not willing to air grievances on Twitter. https://t.co/hxEeWEpI2O

— Joe Crowley (@JoeCrowleyNY) July 12, 2018

Ocasio-Cortez’s victory sent shockwaves through the Democratic Party. Crowley, the House Democratic Caucus chairman, was the first incumbent Democrat to lose a primary this year. The flurry of tweets from both contenders indicated Crowley has not yet spoken with Ocasio-Cortez since losing to her more than two weeks ago.

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Ocasio-Cortez accused Crowley of continuing to run as the Working Families Party candidate in November.

“Now, he’s mounting a 3rd party challenge against me and the Democratic Party- and against the will of @NYWFP,” Ocasio-Cortez tweeted.

She linked to a New York Times article that cited a Working Families Party state director who asked the Crowley campaign to act to remove his name from the party’s line on the November ballot, which the congressman declined.

A Crowley campaign aide told Roll Call on Thursday that the only ways to remove one’s name from the general election ballot are if the candidate dies, moves out of the state, is convicted of a crime or runs on the same party line for a different office. 

The Working Families Party encouraged Crowley to run on its line for Montgomery County clerk in upstate New York, the aide said. Crowley does not intend to do so. A Democrat is also running for that office.

“Joe Crowley truly feels it is unethical to run for an office you don’t plan on serving in, in a place you do not live,” the aide said.

The Working Families Party responded that such a move would be legal.

“The New York State Court of Appeals has found that it is standard for parties to substitute candidates after a primary election, and that the practice does not violate the letter or the spirit of the law,” party counsel Alex Rabb said. “I respect Congressman Crowley’s concerns, but there are common, straightforward and legal ways to remove candidates from the ballot in cases like this.”

Bill Lipton, New York state director for the Working Families Party, said it was “disappointing” that Crowley would not act to remove his name from the 14th District ballot, suggesting he was disrespecting the party and Ocasio-Cortez.

Lipton encouraged Crowley in a statement to change his residency to Virginia. Ocasio-Cortez sharply criticized Crowley during the primary for moving his family to the commonwealth. Lawmakers sometimes do so to be close their families while serving in the nation’s capital.

Crowley’s campaign aide said the congressman would not be changing his residence to Virginia. 

Ocasio-Cortez also unintentionally won the Reform Party line in a neighboring congressional district when a handful of people wrote in her name, but she said she will remain in the 14th District. She can simply decline the the nomination because it was a write-in victory, according to The New York Times.

The prospect of Crowley remaining on the ballot in November escalated tensions between the two, after initial public statements of respect. Crowley performed the Bruce Springsteen song “Born to Run,” which he dedicated to Ocasio-Cortez, the night of his defeat. Ocasio-Cortez said in media interviews after her win that she respected Crowley and appreciated his graciousness. 

“So much for ‘Born to Run,’” Ocasio-Cortez tweeted Thursday. “If you want to see me in Congress, we need your help now more than ever. We cannot underestimate the power of dark money. Support me now,” she added, including a link to her fundraising page.

So much for “Born to Run.”

If you want to see me in Congress, we need your help now more than ever. We cannot underestimate the power of dark money. Support us now: https://t.co/piU7pXr9CU — Alexandria Ocasio-Cortez (@Ocasio2018) July 12, 2018

Crowley also said their inability to connect on the phone was because Ocasio-Cortez’s team had not responded.

“I’d like to connect but I’m not willing to air grievances on Twitter,” Crowley tweeted.

Crowley had said in a debate on NY1 before the June 26 primary that he would back Ocasio-Cortez if she won.

“I’m willing to make the pledge tonight that if you win this primary and have the support of the people of the 14th Congressional District, that I will fully endorse, work for your, and vociferously and robustly work for your election to Congress,” he said at the time. 

Crowley asked Ocasio-Cortez to make a similar pledge, and she said she would have to consult her supporters before answering.

“I represent not just my campaign, but a movement,” she said at the debate. “We govern ourselves democratically. So I would be happy to take that question to a vote and respond in the affirmative or however they respond.”