NEW YORK (AFP) - Manchester United have become the world's first sports team to be valued at more than US$3 billion, according to Forbes magazine.

A recent surge in the stock price of the English Premier League outfit has boosted the team's value to US$3.3 billion (S$4.1 billion), a story posted on the magazine's website reported.

United's most recent quarterly report four months ago listed their long-term outstanding debt at US$560 million.

Shares of the team were offered to the public last August at US$14 but are just under US$17, boosting the wealth of the Glazer family, which has voting control of almost all of the team.

Famed investor George Soros was among those who purchased a stake in the 19-time English champions after shares went public.

Earnings dropped in the first quarter due to reduced television revenue, but Forbes credited the stock boost in part to bright prospects from new sponsor deals with China Construction Bank and Japan's Kansai.

American football outfit Dallas Cowboys were second on the Forbes list, valued at US$2.1 billion.