Mexico's finance minister on Thursday launched a libel writ against TV Azteca's chairman Ricardo Salinas Pliego, escalating a dispute over allegations that Mexico's second-largest broadcaster violated US and domestic securities law in a transaction that made its chairman $100m.

Mexico's National Banking and Securities Commission (CNBV) has announced it will fine the company and directors just 27m pesos ($2.4m) for eight violations of Mexican securities law.