TV host Dermot O'Leary will face no further action after he swore on live TV during his dance marathon in aid of Comic Relief.
The broadcaster, who recently left his job hosting The X Factor on ITV, raised more than £600,000 for good causes by dancing for 24 hours.
But 18 hours in to his marathon effort, he greeted a friend outside New Broadcasting House in central London by saying: "How f***ing fantastic to see you."
Communications watchdog Ofcom noted that the Irish-born presenter apologised within a minute and the BBC broadcast a further apology shortly afterwards.
The BBC told Ofcom it had warned all its guests not to swear, adding that O'Leary was "aware he was wearing a live microphone and that the event was being broadcast live".
The Ofcom report noted: "However, given the event had begun at 19:00 the previous evening and by the time of the incident at 13:30 the next day, the BBC said Dermot O'Leary was very tired having been dancing for over 18 hours and throughout the night."
The watchdog's spokesman said: "After carefully investigating this programme, Ofcom took into account that the BBC had issued two apologies immediately after the offensive language was aired. As a result, we consider the matter resolved."