Nelly's clothing label made $20m (�11.4m) in 2002

The two members, James Tyrone Wilson and Cameron Caines, are suing the singer for trademark infringement and unfair competition.

The rapper's clothing label made more than $20m (�11.4m) in 2002.

Wilson and Caines said they had exclusive rights over the name Vokal and had recorded under it since 1994.

The singers also want Nelly to stop using the name and are seeking an injunction. The suit is expected to claim millions in damages.

No comment has yet been made by Nelly or his representatives.

'Eight figure' damages

"Right now, since we don't have an accounting of the profits, we can't completely quantify the damages," Michael Santucci, the group's lawyer, said.

He said he expected the Vokal members to ask for a "seven or eight-figure number" in damages because of the money the clothing label had made in 2002.

Figures for how much it had made in 2003 were not available.

According to their lawsuit, which was filed in Orlando, Florida, Vokal had written music, performed live, recorded songs and distributed clothing under the name since 1994.

In 1998 they signed a deal with Universal Records, which also signed Nelly at the same time.

Wilson and Caines said they had retained exclusive right to the use of the name, and Nelly was aware of their music and their business activities.