"It is time the Lanka-centric approach of the external affairs ministry is changed to a Tamil welfare-centric approach," AIADMK leader V. Maitreyan said in the Rajya Sabha.
"As far as we Tamils are concerned, Sri Lanka is an enemy country, and it will remain so until justice is meted out to the Tamils," he said.
He said there was "a general perception" that the Indian foreign ministry was run by diplomats "whose mindset needs to be changed".
Maitreyan placed in the house a report by Human Rights Watch on sexual violence in Sri Lanka and a CD of a Channel 4 documentary on human rights abuses in that country.
He also submitted photographs of the 12-year-old son of the late Tamil Tigers chief Velupillai Prabhakaran who is said to have been captured and shot dead in cold blood by the Sri Lankan military.
Maitreyan alleged that there was no accountability to the "war crimes" committed in Sri Lanka during the final phase of the war that crushed the Tamil Tigers in May 2009.
Echoing much of what Tamil Nadu Chief Minister J. Jayalalitha has stated earlier, the AIADMK MP insisted that Sri Lanka was in no position to probe the alleged "war crimes".
"A country which does not have an independent judiciary cannot investigate itself."
He urged India to move a single-line resolution in the UN condemning the "genocide" of Tamils in Sri Lanka and sought an economic embargo against Colombo.
Maitreyan took a dig at the DMK, saying any amount of conferences and meetings with foreign diplomats in New Delhi on the Sri Lanka issue "will not wash away the sins of the past".
His reference to the DMK's failure to put pressure on the Congress-led government to end the punishing Sri Lankan military offensive against the Tigers drew vocal condemnation from DMK members.
"All that you have to do," Maitreyan said, looking at the DMK members, "is to force the UPA government to act, and to act firmly in Sri Lanka".