India's National Security Advisor M.K. Narayanan summoned Sri Lanka's representative in New Delhi on Monday to convey strong reservations about the intensifying military onslaught against Tamil separatists, officials said.
The 80 million population of India's southern Tamil Nadu state share cultural and emotional links with minority Tamils in Sri Lanka.
Narayanan said that "the escalation of hostilities in the north and the resultant fall out was leading to a great deal of concern in India," an Indian foreign ministry statement said.
Sri Lanka must "act with greater restraint and address the growing feeling of insecurity among the minority community," it said.
India directly intervened in the Sri Lankan conflict in 1987 by sending troops to supervise a bilateral peace pact, but the soldiers ended up fighting Tamil Tigers.
New Delhi withdrew its troops three years later after losing 1,200 soldiers.