In a statement, Italian Defence Minister Lorenzo Guerini welcomed the "positive outcome" for Salvatore Girone and Massimiliano Latorre.

News agencies said it followed an assessment by prosecutors last month that there was not enough evidence for a trial.

"This brings to an end a years-long event during which the defence ministry has never left the two marines and their families on their own," Guerini said.

Girone and Latorre shot dead the unarmed fishermen off the southern Indian coast in February 2012 while protecting an Italian oil tanker as part of an anti-piracy mission.

After a legal saga that has dogged relations between Rome and New Delhi for almost a decade, India in April 2021 accepted a compensation offer of 100 million rupees ($1.4 million, 1.1 million euros).

Quashing the case in June, India's Supreme Court ruled that 40 million rupees each would be given to the families and the remaining 20 million rupees to the owner of the boat used by the fishermen.

But it said that the Italian government must start criminal proceedings against the two marines under its jurisdiction immediately and that the Indian authorities would provide evidence in the case.

Italy had argued the marines were in international waters and had fired on the fishing boat because it failed to heed warnings to stay away.

India called it a "double murder at sea" and arrested and charged Girone and Latorre -- members of Italy's elite San Marco Marine regiment -- with homicide.

Italy in 2015 took the case to the Permanent Court of Arbitration (PCA) in The Hague, which ruled last year that the marines were entitled to immunity.

In 2016, the same tribunal allowed Girone, who had been holed up in the Italian embassy in New Delhi, to return to Italy. Latorre had already returned home two years earlier for treatment after a stroke.