Italy makes no progress in marines talks with India
Mogherini meets Khurshid in The Hague
25 March, 16:25
It is also planning to try to have international arbitration on the case, which has seriously strained Indian-Italian relations, especially before prosecutors ruled out the death penalty as a possible sentence earlier this year.
They now face up to 10 years in prison, prosecutors say.
Italy argues that the case sets dangerous and wide-ranging precedents for any country involved in anti-piracy missions overseas.
The incident occurred while the marines were guarding the privately owned Italian-flagged oil-tanker MT Enrica Lexie off the coast of the southern Indian state of Kerala in February 2012.
The pair have been living and working at the Italian embassy in India amid a long series of delays in the case.
Rome says the marines should be allowed to return home and argues India does not have jurisdiction over the case as the incident took place outside its territorial waters.
"We reiterated our determination to explore all the political and legal actions (possible) to see our rights recognised and to exercise jurisdiction over the marines case," said Mogherini.