"This sounds like an issue between India and Italy, not an issue for us," State Department spokesperson Victoria Nuland told reporters at her daily news conference.
Two Italian marines Massimiliano Latorre and Salvatore Girone, who are accused of killing two Indian fishermen last year, had been given permission by the Supreme Court to fly to Italy to cast their votes in the polls on the understanding that they would return.
The two marines were allowed by the court to go to Italy after Italian envoy Daniele Mancini had given an assurance to send them back.
The apex court has now asked the Italian Ambassador not to leave the country without its permission, taking exception to his government's refusal to send back the two marines.