Anthony Weiner Resigning (VIDEO)

WASHINGTON – Embattled Rep. Anthony Weiner (D-N.Y.) will resign, sources confirmed to The Huffington Post, making him the first Congressman whose career was wrecked by indiscretions on Twitter.

Weiner, who mistakenly tweeted a photo of his underwear-clad erection last month and then lied to cover it up, has been under escalating pressure to quit as one embarrassing revelation after another came to light. The New York Times was first to report on Thursday that he had succumbed to that pressure.

Congressional leaders had been slated to meet Thursday to hash out a strategy regarding Weiner's fate. Most of the House leadership had already called for his resignation, and President Obama made a similar suggestion in an interview Tuesday.

A day after Obama's comments, Weiner's wife, Huma Abedin, returned from a weeklong trip to Africa with her boss, Secretary of State Hillary Clinton. Also on Wednesday, former porn actress Ginger Lee, who had exchanged emails and messages with Weiner, held a bizarre press conference in which she claimed he had urged her to lie about their communication.

The congressman had already announced he would be taking a two-week leave from the House in order to enter a treatment program. The combination of family pressure and personal embarrassment apparently became too big a hurdle to overcome. It was recently reported that Abedin is pregnant with the pair's first child.

“At least the nightmare is over,” one source close to Weiner said.

Another told The Huffington Post that Weiner called Democratic Congressional Campaign Committee Chairman Steve Israel (D-N.Y.) Wednesday, informing him of his plans.

Observers noted the decision had to have been extremely hard for Weiner, who defiantly resisted pressure to resign for several weeks, and that the call to Israel came the day Abedin got home.

“Wife comes home and he picks ‘us’ over ‘me’ –- but I'd take away his belt and his shoelaces, just in case,” said Baruch College political scientist Doug Muzzio.

House Minority Leader Nancy Pelosi (D-Calif.), who had been among those trying to push Weiner out, declined to discuss him at her weekly news conference, suggesting it was just her regular update -- a statement met with chuckles from reporters who at first thought she was joking.

But she was not.

"if you're here to ask questions about Congressman Weiner, I won't be answering any," Pelosi said.

Weiner is expected to resign during a press conference in New York on Thursday afternoon.

UPDATE 12:03 p.m. -- Rep. Nita Lowey (D-N.Y.) issued the following statement on Weiner's expected resignation:

"There is life after Congress for Anthony Weiner and I hope he devotes himself to repairing the damage he caused to his personal life.”

UPDATE 1:00 p.m. -- House Democrats from New York and neighboring states offered varying opinions regarding whether Weiner should be resigning over the scandal.

“His life and breath was here, outside of his family,” said Rep. Bill Pascrell (D-N.J.), who wouldn’t say if he has spoken to Weiner this week.

Turning to a reporter, Pascrell continued, “Just picture yourself if they took that pencil and pad away from you and said, ‘Because of this thing, you didn’t break any laws, you can’t write anymore. You have to find something else to do.’ You know, it’s an empty feeling.”

“A lot of folks that knew him, we have empty feelings. But we get up and do the job that we’re paid for,” he said.

Democratic Congressional Committee Chairman Steve Israel (D-N.Y.) also wouldn’t comment on his conversations with Weiner and said he would have more to say after Weiner’s press conference. But Israel said his position on the matter has been clear all long.

“I’ve had repeated conversations with Congressman Weiner in which I expressed my strong feelings that he should resign for the good of himself, his family, Members of Congress and the country,” he said.

Rep. Rob Andrews (D-N.J.) commended party leaders for the way they have dealt with the situation and concurred that Weiner is doing the right thing by stepping down.

“I think our leadership handled this very well, and if Mr. Weiner is resigning I think he ultimately handled it well as well,” he said.

A Democratic leadership aide summed up the ordeal as “a political witch hunt” but suggested that Weiner's resignation won't be a huge blow for the party in the long run.

Losing Weiner is “not that big of a deal, but he was good,” said the aide. “Not going to affect control of the House.”

Jen Bendery contributed reporting.