Emma Watson has said that she is glad she had her knickers on during the premiere of new Harry Porter film in London, where she suffered wardrobe malfunction.

The actress, who accidentally flashed her lower undergarment when gust of wind lifted her dress on the rainy day, spoke to US chat show host David Letterman about the incident.

“At least I’m wearing underwear!” she quipped, making the audience roar with laughter, the Daily Star reports.

However, the actress was quick to dismiss the occurrence as not something harmful to her image.

She said: “This was a small wardrobe malfunction – that happens.”

The19-year-old admitted that she is still in the process of learning things in Hollywood.

She added: “I’m still learning, I’m still learning!”