Prime Minister Narendra Modi on Friday night said India stands by the people of the island nation and that ships are being rushed with relief material, with floods and landslides causing widespread devastation in Sri Lanka.
He condoled the death of 90 people due to rain-triggered floods and landslides in Sri Lanka.
"We stand with our Sri Lankan brothers and sisters in their hour of need", he said in a tweet.
Modi said Indian ships are being dispatched with relief material.
"The first ship will reach Colombo tomorrow morning. The second will reach on Sunday. Further assistance on its way", he said in a series of tweets.
Heavy floods and landslides killed around 92 people in the country
Heavy floods and landslidestriggered by the worst rainfall since 1970s have killed atleast 92 people and left 110 missing in Sri Lanka, officials said Friday, warning the situation could get worse.
Over 20,000 people have been displaced in seven districts as the south western monsoon caused havoc, destroying hundreds of homes and cutting off several roads.
"We have seen worst rainfall since the 1970s", said Dunesh Gankanada, deputy minister of Disaster Management Centre (DMC).
"We are carrying out relief operations in some areas when we can't even reach some of the affected areas", Gankanda said, adding that people in the southeastern region of Ratnapura were taking shelter on tree tops.
The DMC said the death toll has risen to 92 and another 110 remain missing with reports coming in from areas which were inaccessible earlier in the day.
The government has alerted international organisations for relief, Gankanda said.
"The Ministry of Foreign Affairs will keep monitoring the situation and will seek assistance as required", said Deputy Minister Karunaratne Paranavithana.
Sri Lanka Airforce and the Navy are working to provide relief to people stranded by floods with helicopters and boats deployed, an official has said.
Relief officials said the monsoon had been expected, yet the rainfall recorded was at unexpected levels.
Over 600 millimeters of rain was recorded in some areas with other badly affected areas receiving rainfall ranging between 300 and 500 millimetres.
Chief of Meteorological Department R S Jayasekera said while the peak of the monsoon had passed, more rains are expected during the next few days. Jayasekera said it is expected to intensify again on May 30.
He said the rainfall was more than in 2003 in the south of the island which killed over 250 people.
A majority of those killed were from a landslide in Kalutara and flooding in Ratnapura district, officials said.
They said adverse weather had badly affected seven districts.
According to DMC, a total of 7,856 individuals from 2,811 families were affected in the Sabaragamuwa, Western and Southern Provinces due to the torrential rains which have been lashing several parts of Sri Lanka since yesterday.
"The number of deaths in Ratnapura district is recorded as 10 and it's nine in Kalutara due to floods and landslides", the DMC said earlier in a report.
According to the report, Galle is the worst affected district where 7,157 people have been affected.
Kalutara District Secretariat Field Officer said 38 deaths were reported from the district alone.
The Centre has asked people to be vigilant on rising water levels and also advised them to evacuate from unstable slopes if the showers continue for the next 24 hours to minimise disasters due to landslides, rock falls in Kegalle, Galle, Kalutara, Matara, Hambantota districts.
"People of Bulathkohupitiya, Deraniyagala, Yatiyantota, Dehiowita, Baddegama,Yakkalamulla, Neluwa, Thawalama, Bulathsinhala, Agalawatta, walallawita, Baduraliya, Kotapola, Pasgoda, Pitabeddara, Mulatiyana, Walasmulla and Katuwana areas are advised to evacuate", the report said.
"Showers or thundershowers will occur at times in the Western, Sabaragamuwa, Southern, Central and North-western provinces. Heavy falls (about 150 mm) can be expected at someplaces", it said.
Sri Lanka, which has been heavily deforested for cashcrops, often witnesses landslides during the monsoon season.
Last year, more than 100 people were killed in a massive landslide in the country.