Other than death toll, it can not be said how many people have been affected by the calamity.
More than 2,000 military personnel from the army, navy and air force were already undertaking a ceaseless coordinated operation to reach trapped villagers and evacuate those residing in areas likely to be hit by potential mudslides, he added.
Earlier, the head of military rescue operations Major General Sudantha Ranasinghe told the BBC that troops had reached all the affected areas and the risk to life had receded.
Pakistan said it was in talks with Sri Lankan authorities to identify its needs.
Meanwhile, to help victims of the worst flooding in last 14 years, neighbouring country India has dispatched two ships with medical teams and other emergency relief materials.
In addition, 113 people were reported missing, a government spokesman said.
Seven districts have been severely affected, the worst of which is the coastal Kalutara, where 38 people have died and 80 people are missing. "The government will give new houses to those who lost their houses", the President said on twitter.
An Indian naval ship arrived in Colombo, the nation's capital, with relief supplies.
India stands by the people of the island nation and that ships are being rushed with relief material, the PM said.
The flooding is the worst since May 2003 when 250 people were killed and 10,000 homes destroyed after a similarly powerful monsoon, officials said.
The DMC said the latest monsoon ended a prolonged drought that had threatened agriculture as well as hydropower generation.
"The monsoon has firmly established and we could have evening showers at a lesser intensity", department chief S. R. Jayasekera said.
According to the Disaster Management Center (DMC) sources the total number of displaced persons due to the disaster situation has increased up to 493,455.