Ms Rao is expected to discuss in Colombo the recent killings of Indian fishermen

The Sri Lanka navy (SLN) is accused of killing at least two fishermen during the past month. Sri Lanka authorities deny the accusation.

But villagers in southern India blamed the Sri Lankan navy after the recent deaths of two of their fishermen in separate incidents.

"India has already reacted very strongly to the incidents in which two Indian fishermen were killed in the span of one month, notwithstanding Sri Lankan government's claim that its navy was not involved," a report in state-run Doordarshan said.

Temple attack

In the recent incident, a fisherman was killed and two others were injured while fishing on 22 January.

The man died after Sri Lankan Naval personnel allegedly tied a rope around his neck and pushed him into the water State-run Doordarshan

"The man died after Sri Lankan Naval personnel allegedly tied a rope around his neck and pushed him into the water," Doordarshan said quoting official sources.

The BBC's Sanjoy Majumder in Delhi says the issue could lead to a diplomatic row between two friendly neighbours.

On Monday, an unidentified group had stormed the Mahabodhi Temple in Chennai and assaulted devotees and Buddhist monks.

After the incident, the Sri Lankan government has asked India to ensure that Sri Lankan people and organisations in southern India are safe, after several Sri Lankan Buddhist monks were injured in the attack.

Demonstrations also forced two prominent Sri Lankan cricketers, Sanath Jayasuriya and Aravinda de Silva, to withdraw from a match in the city.