The Minister of State for Human Resources Development denounced the manner the two marines have behaved after leaving India.
"We have time till 22nd of March to see if the two return. If they don't, then the Italian ambassador's position becomes untenable because it was he who has given the undertaking that the two will return," said Tharoor.
"Yes, this would then become a serious issue and it would have legal, moral and diplomatic overtures," he told the media. "I don't think such a situation has ever risen."
Marines Lattore Massimillano and Salvatore Girone shot dead two Indian fishermen, Ajesh Binki and Gelastine, February 15 last year, allegedly mistaking them for pirates.
In December, they were allowed to travel to Italy for Christmas, after which they returned ahead of schedule early this year. The apex court then ruled that they can be tried in Delhi.
Last month, they got the Supreme Court's permission to go to Italy to vote in elections. This time, the Italian government refused to send them back, triggering a diplomatic row.
Thiruvananthapuram: Italian Ambassador Daniele Mancini's position will become untenable if the two Italian marines don't return to India, central minister Shashi Tharoor said on Friday.
First Published: Friday, March 15, 2013, 21:30