The American pop star, dressed in typically flamboyant style in a black suit and a wig with three white roses attached, said she had been taken aback by the huge crowd that came to hear her in the central city of Taichung on Sunday.

It had officially been declared "Lady Gaga Day" in her honour, with 6,000 people packed into an open air theatre on a humid night and another 40,000 watching on a huge screen outside.

"I had such a wonderful time last night. I couldn't believe so many people came there," she told hundreds of eager reporters squeezed into the ballroom of a hotel in Taipei.

Organisers had previously expected a turnout of 4,000 fans -- known as "Little Monsters" -- at the gathering, which was part of a promotional tour of Taiwan for her new album "Born This Way".

"I played almost an hour and 20 minutes. Normally my concert was about two hours, so the performance last night was almost a full concert," Lady Gaga said, adding that she had sung nine songs rather than four.

Asked if she had any plans to come back to Taiwan soon, she said: "I'll tour all over Asia. I promise... I will be back and you'll see a full show."

The 25-year-old diva, ranked this year's most powerful celebrity by Forbes magazine, is among the most popular international entertainers in Taiwan and her visit made the front pages of major newspapers.

She was to leave Taiwan late Monday, one day earlier than scheduled, organisers said. She takes in Singapore next.

Copyright AFP (Agence France-Presse), 2011