Sir John Eliot Gardiner, one of the world's most prominent conductors, has pulled out of the BBC Proms after being accused of assaulting a singer.
He allegedly punched William Thomas, a bass, because he left the podium in the wrong direction at a concert in France.
In a statement, Sir John said he "deeply regretted" losing his "temper".
He added that he understood "how much this has affected all the participants involved in this major project, which has been so dear to my heart".
"I make no excuses for my behaviour and have apologised personally to Will Thomas, for whom I have the greatest respect. I do so again, and to the other artists, for the distress that this has caused."
A spokesperson for Mr Thomas had earlier confirmed the incident to the BBC, saying: "All musicians deserve the right to practise their art in an environment free from abuse or physical harm."
Sir John, 80, withdrew from his performance at the Festival Berlioz in La Côte-Saint-André, south eastern France, on Wednesday night.
In a statement, the BBC said Sir John had also "decided to withdraw from the performance of [Berlioz's] The Trojans at this year's BBC Proms."
Sir John's assistant, Dinis Sousa, will take his place for that concert, and all remaining performances of The Trojans on the Monteverdi Choir's European tour.
A spokesperson for the Monteverdi Orchestra said: "We continue to look into the events that occurred on Tuesday evening.
"Our values of respect and inclusivity are fundamental to us as a company and we take seriously the welfare of all our performers and employees."
News of the alleged altercation first emerged on music website Slipped Disc, which said it had received multiple reports of an incident that took place backstage in France on Tuesday night.
A representative for Sir John told the website that the conductor had been suffering from extreme heat.
Mr Thomas did not appear to be seriously injured, and took to the stage on Wednesday evening in France.
Bruno Messina, the festival's artistic director of the Festival Berlioz, said in a statement that he was "devastated by the incident", but felt it was important that Wednesday's show took place.
'Reflect on my actions'
The BBC had previously said it was investigating the matter.
"We take allegations about inappropriate behaviour seriously and are currently establishing the facts about the incident," said Proms organisers in a statement.
Sir John, from Fontmell Magna, Dorset, is a leading figure in the period-instrument movement, who is famous for his interpretations of Baroque music, specialising in composers such as Monteverdi, Bach, Mozart and Beethoven.
He established prestigious ensembles including the Monteverdi Choir, the English Baroque Soloists and the Orchestre Révolutionnaire et Romantique, and has conducted many of the world's leading orchestras, including the Berlin Philharmonic, London Symphony Orchestra and Boston Symphony Orchestra.
Many of his recordings are considered classics - including his complete Beethoven Symphonies, and a live recording of Bach's St John's Passion - and his 2013 book Bach: Music in the Castle of Heaven, was well received by critics.
Earlier this year, Sir John featured at King Charles's Coronation, where he led the Monteverdi Choir and English Baroque Soloists in a pre-service concert at Westminster Abbey.
Concluding his statement on Thursday, Sir John said: "I know that physical violence is never acceptable and that musicians should always feel safe.
"I ask for your patience and understanding as I take time to reflect on my actions."