"I can tell you that if it was me, I would resign," Obama told Ann Curry in an interview in North Carolina to be aired on NBC's "Today" show Tuesday morning.
"When you get to the point where, because of various personal distractions, you can't serve as effectively as you need to, at the time when people are worrying about jobs, and their mortgages, and paying the bills, then you should probably step back," the president said.
Earlier Monday, multiple media reported that the release of more embarrassing photos may push Weiner to resign, citing sources close to him.
WCBS-TV, New York, and the New York Daily News both cited unnamed sources saying the U.S. House Democrat's determination not to quit is weakening.
During the weekend, TMZ.com published more cellphone self-portraits of Weiner, apparently taken in the House gym. Several show him showing off his naked body holding only his camera and his privates. In others, he is draped in a towel, flexing his muscles in the locker room mirror.
TMZ said the photos were sent to at least one woman. Since they were taken in the House gym, his use of public resources could pose an ethics issue.
Furthermore, besides his admitted online sex chats with several women in recent years, word came out that Weiner also sent messages via Twitter to a 17-year-old girl in Delaware, although she said the contents were not suggestive.
On Saturday, the congressman said he was taking a "leave of absence" to get psychiatric help.
Aboard Air Force One Monday, White House press secretary Jay Carney said Obama considered Weiner's behavior "inappropriate" and the matter a "distraction" but did not call for his resignation.
The second-ranking House Democrat, Steny Hoyer of Maryland, joined Minority Leader Nancy Pelosi, D-Calif., in calling for Weiner to quit Sunday.
One source said one of the few people who could sway Weiner is his predecessor and mentor, Sen. Chuck Schumer, D-N.Y. Schumer has said he is "heartbroken" but has stopped short of telling him to go.
Weiner's pregnant wife, Huma Abedin, is in Africa with her boss, Secretary of State Clinton. He is said to be still convinced she won't divorce him and even wants him to stay in Congress.
Staffers say Weiner probably will make no decisions until his wife returns home Wednesday.