World number ones Andy Roddick and Justine Henin-Hardenne have been named 2003 ITF world champions, the International Tennis Federation said on Monday.

American Roddick, 21, earned the award after winning his first Grand Slam crown at the U.S. Open in September as well as reaching the semi-finals at the Australian Open and Wimbledon.

Belgian Henin-Hardenne, also 21, was twice a Grand Slam winner in 2003, beating her compatriot Kim Clijsters to clinch both the French and U.S. Open titles.

"The selection of the ITF men's world champion was a very difficult decision," ITF president Francesco Ricci Bitti said in a statement.

"Both Andy Roddick and Roger Federer turned in excellent years but, in the end, Roddick's superior performance at the Gand Sams and in the Masters Series gave him a slight edge over Federer."

Swiss Federer, 22, won Wimbledon and the season-ending Masters Cup before finishing the year ranked second behind Roddick.

Bob and Mike Bryan were named ITF men's doubles champions, the American brothers having won the French Open and the Tennis Masters Cup, as well as reaching the final at the U.S. Open.

Spain's Virginia Ruano Pascual and Argentina's Paola Suarez won the women's award for the second successive year after winning the U.S. Open and the WTA Tour Championships.

The pair were also finalists at the Australian Open, Roland Garros and Wimbledon.