New Delhi is planning to send three war ships with a combined force of up to 3,000 security personnel because of fears that Tamil Tiger rebels could stage land, sea or air attacks, diplomats and officials said.
"Given the security situation in Colombo, it is important for India to address all possibilities because the Prime Minister (Manmohan Singh) will be attending," a top diplomatic source said.
He said war ships with helicopters will be anchored off Sri Lanka's coast in case the island's only international airport was forced to shut.
The airport has been attacked several times by the rebel Liberation Tigers of Tamil Eelam (LTTE).
Sri Lanka has closed its air space and diverted regular commercial flights to neighbouring India and the Maldives when the Tigers flew their light aircraft on bombing missions in Colombo and elsewhere.
The Tigers also operate a fleet of speed boats and have staged attacks against Sri Lankan ports.
Diplomats said security arrangements for the ei