Jason Manford has resigned from The One Show after admitting that he shared sexual internet messages with female fans.
The 29-year-old comedian handed his resignation notice to bosses on the flagship show last night, just four months after taking the coveted presenting role.
He said in a statement: "I have decided after careful consideration to step down from The One Show to concentrate on my family and tour commitments."
The BBC said: "We have got nothing to say except that we accept Jason's decision."
Speaking to The Sun, Manford admitted he had "flirted" with 10 or 12 people online which "went over the line with a few".
The comic told the newspaper: "There were 10 or 12 people flirting and then with a few it went over the line. We would start off flirty, then innuendo and then a bit saucy. They were moments I thought 'I shouldn't be saying that'."
The 7pm BBC One flagship show is not due to be screened on Friday because of the Children in Need charity telethon - for which Manford had pre-recorded material - and the next show he was due to present is on Monday. However, his resignation is believed to come into effect immediately and he is not expected to present the show again.
Manford said: "I don't drink, I don't do drugs, so it's not like I've got those to blame. I have my own stupidity to blame. I've never felt so low."
Referring to his wife Catherine, he added: "We have had a serious sit-down about it and agreed that what we've got is worth fighting for. She's fine and we're fine."
He said he felt he had let his family down and, after showing his wife the Twitter messages, she was "disappointed".