Under the new rules men are permitted to wear suits that extend from the naval to above the knees, while women's suits must have a bare neck and shoulders and end above the knees.

It is unclear exactly when the new rules will be introduced.

'The rules will be applied in 2010. That can be April or May. It depends on the time manufacturers need to pass from polyurethane to textiles,' the FINA executive director Cornel Marculescu said.

The FINA Congress had earlier adopted with an overwhelming majority such a proposal put forward by US swimming.