Beyoncé has admitted miming her rendition of the American national anthem at last month's Obama inauguration.
She told journalists in New Orleans - ahead of Sunday's Super Bowl - that she was a "perfectionist" and - due to lack of rehearsal time - "did not feel comfortable taking a risk".
"I wanted to make him [Obama] and my country proud, so I decided to sing along with my pre-recorded track," she said. "I'm very proud of my performance."
The star opened the press conference in New Orleans by asking reporters to stand as she performed a live rendition of the US national anthem.
"I am a perfectionist and one thing about me is that I practise until my feet bleed and I did not have time to rehearse with the orchestra," she said.
She added that her decision to mime was triggered by the weather, delays and "no proper soundcheck", adding that pre-recording is "very common in the music industry".
"It was a live television show and a very, very important emotional show for me and one of my proudest moments," she said.
However, she insisted she would be singing live for her half-time performance on Sunday's Super Bowl - one of the most-watched TV events in the United States and on a global level.
"I will absolutely be singing live," she insisted. "This is what I was born to do, it is what I was born for."