"I think Charlie Rangel served a very long time and served his constituents very well, but these allegations are very troubling," Mr. Obama said.
In an interview with CBS "Early Show" Anchor Harry Smith for "Sunday Morning" and Monday's "The Early Show," the president all but said Rangel should resign from Congress.
"He's somebody who's at the end of his career, 80 years old," Mr. Obama said. "I'm sure that what he wants is to be able to end his career with dignity, and my hope is that happens."
After Rangel and his lawyers would not agree to a settlement which would have required him to admit to at least some of the allegations against him, the ethics committee announced 13 formal charges Thursday.
A half-dozen Democrats in Congress have already called for Rangel to resign. They are clearly fearful that a trial - beginning in September and lasting for weeks - could have a devastating effect when voters go to the polls in November.
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Making matters worse, unrelated ethics charges have also been filed against Democrat Maxine Waters of California, which could lead to a second trial this fall.
Despite the nudge from Mr. Obama, there's no indication that Rangel, who's already lost the chairmanship of the Ways and Means Committee, is prepared to take the next step and resign.
Whether Rangel will survive is unknown. An admonishment like that from a president would torpedo just about any other politician but don't bet against Rangel, who by all accounts doesn't really care what the president thinks.
Besides, New York congressional delegation still supports him. So does the Congressional Black Caucus. Some members are very upset that the first black president took such an usually public cudgel to one of the caucus's founding members.