Consumer group Adusbef plans to fight Italian banks' use of a certain type of compound interest on loans, in what could lead to Italy's first class-action lawsuit, a statement from the group said.

A recently enacted law will allow class-action lawsuits -- commonplace in the countries such as the United States -- to be filed in Italy starting July 2008.

Adusbef, which focuses on financial services matters, wants to take aim at the so-called practice of anatocism, where compound interest is calculated on the initial loan plus interest that is accumulated each time the money comes due.

"We want to start from the most hated banking practice, this form of usury that is known as anatocism," Adusbef said.

That is opposed to using simple interest, in which only the interest on the original money borrowed is added.

Although banned by the Italian civil law code, Italian banks have been using compound interest for over 50 years, Adusbef said. No-one at Italian banking association ABI was immediately available for comment.