Anger erupted in India Tuesday over Italy's refusal to return two marines facing trial for the killing of two fishermen, with politicians saying Rome is treating India like a "banana republic".
The marines are accused of shooting dead the Indian fishermen off the country's southwestern coast in February last year, when their fishing boat came close to the Italian oil tanker they were guarding.
The marines said that they mistook the fishermen near the port of Kochi for pirates.
The Italian foreign ministry announced Monday that the two marines would not return to India when their court-allowed leave runs out at the end of this month.
India's main opposition Bharatiya Janata Party (BJP) accused the country's Congress-led ruling coalition Tuesday of colluding with the Italian government to ensure that the marines can remain in Italy.
"There is absolutely diplomatic collusion between the Indian and Italian governments," BJP spokesman Prakash Javadekar told AFP.
"This is contempt of the Supreme Court of India. Is India a banana republic? How can the Italians treat India like this?" he asked.
Dora Selestine, the 47-year-old widow of one of the slain fishermen, reacted with disappointment to Italy's decision and urged the Indian government to ensure the marines are brought back for trial.
"I hope that the marines will return and face trial. If they don't, it would be very upsetting," she told AFP.
Italy insists the marines should be prosecuted in their home country because the shootings involved an Italian-flagged vessel in international waters, but India says the killings took place in waters under its jurisdiction.
The case, which was transferred from a local court in India's southern Kerala state to the Supreme Court in New Delhi, has created diplomatic friction between the two countries.
Indian foreign minister Salman Khurshid said Tuesday that India was studying Italy's decision in detail.
"Let us understand their position and we will respond," Khurshid told reporters in New Delhi.
The Italians were allowed to go home last month by India's Supreme Court to vote in February 24-25 national elections, on condition that they returned to face trial once their four-week leave expired.
But the Italian foreign ministry said that Massimiliano Latorre and Salvatore Girone will not go back to India in view of the "formal international controversy" between the two countries.
The marines were granted special permission once before to return home to Italy for Christmas, but later came back to India.
Armed guards are increasingly deployed on cargo ships and tankers in the Indian Ocean to tackle the threat posed by Somali pirates, who often hold ships and crews hostage for months demanding multi-million-dollar ransoms.