SEOUL?South Korea's top female pop group the Wonder Girls will soon have a new line-up, their agent announced Saturday, after taking the US pop charts by storm.

Sunmi, 18, will leave the five-member group when they wrap up their year-long tour of the United States in February, JYP Entertainment said.

According to the Billboard website (www.billboard.biz), "Nobody" topped the year-end Hot Singles Sales chart in 2009, beating stars such as Mariah Carey, Lady Gaga and Beyonce.

"Nobody" also ranked 76th in the Billboard Hot 100 in late October, a first for any Asian group, JYP Entertainment said.

Sunmi, who dropped out of school to join the Wonder Girls, will return to her education in March.

"It was such a valuable and happy experience for me to take part in the performance tour to 50 cities in the United States for the past year. But I came to wonder whether I should live like this," Sunmi said in a statement.

Sunmi will be replaced by Hye Lim, 18, who has been groomed by the group's agent for the past three years with a view to appealing to Chinese fans. She is fluent in English, Cantonese and Mandarin,

Debuting in early 2007, the group scored three consecutive number one hit singles with "Tell Me," "So Hot" and "Nobody."

The Wonder Girls, also including Sohee, Sunye, Ye-eun and Yubin, plan to launch their first English album in February.