MADRID (REUTERS) - China are cautiously optimistic of winning four gold medals at the world swimming championships starting later this month, head coach Yao Zhengjie said.

The Chinese team competing in Barcelona will be led by double London Olympic champions Sun Yang and Ye Shiwen, organisers said on Wednesday after the Asian nation named their team for the event in Spain.

"According to our results this year and the world rankings, I hope we can claim four golds, as we have four world fastest times," Zhengjie was quoted as saying on the official championships website (www.bcn2013.com).

China finished second behind United States on the medal table at the last worlds in Shanghai two years ago, with five golds, two silvers and seven bronze.

The indoor swimming events begin on July 28 at a specially constructed pool at Barcelona's Palau Sant Jordi, one of the venues for the 1992 summer Olympics.