The trial has raised the prospect that Finmeccanica could be blacklisted in India, the world's largest arms importer and an important growth market for the state-owned aerospace and defence group.

On Monday, a judge in the northern Italian city of Busto Arsizio cleared more than 80 people as possible witnesses, including businessman Ratan N. Tata and former British Defence Secretary Geoff Hoon. Those cleared, however, may not be called to testify.

Prosecutors have accused ex-Finmeccanica Chairman Giuseppe Orsi of paying bribes to intermediaries to secure the 560 million euro ($742.81 million) deal in 2010 when he was head of AgustaWestland, the Finmeccanica unit that sold the helicopters.

Bruno Spagnolini, former CEO of AgustaWestland, is being tried alongside Orsi on the same charges. Both deny wrongdoing.

Defence lawyers requested Hoon and Tata to be admitted as witnesses to provide evidence on the defence industry in India. Antony was being called to give testimony on the tendering process in India.

Antony, who has a corruption-free image that sets him apart from many Indian politicians, was defence minister when the Indian Air Force awarded the contract to AgustaWestland.

He is believed to favour blacklisting the firm but could be outvoted by cabinet colleagues who worry it could hamper defence purchases in the future, several government sources said.

The next hearing in the trial will be on Sept 17.

($1 = 0.7539 euros)

(Reporting by Emilio Parodi; Writing by Danilo Masoni; Editing by Louise Heavens)