"My conscience tells me that you will definitely forgive me as I had to take certain decisions which have put you in a lot difficulty," he said on his radio programme Mann ki Baat.
"Especially, when I look at my poor brothers and sisters, I definitely feel that they must be thinking what kind of a Prime minister is this who has placed us in this situation," he added.
Watch | 'There was no other way': PM Modi apologises to the poor hit by lockdown
"The lockdown is for you to protect you and your family. You have to show this patience for many more days," he added.
Modi has already addressed the nation on the issue of the coronavirus outbreak twice in the last few days.
The Prime Minister had announced a 21-day nationwide lockdown in his address on March 24 as part of the government's stringent efforts to tackle the spread of Covid-19 that has infected nearly 1000 people and killed 25 in India so far.
Before that, he had called for a Janta Curfew on March 22, which was in place for 14 hours as people stayed off the roads and public places during this period.
He announced a new fund for citizens on Saturday, PM-CARES or Prime Minister's Citizen Assistance and Relief in Emergency Situations Fund, in an emergency situation as the magnitude of the crisis due to the outbreak of coronavirus unfolds.
"People from all walks of life expressed their desire to donate to India's war against COVID-19. Respecting that spirit, the Prime Minister's Citizen Assistance and Relief in Emergency Situations Fund has been constituted. This will go a long way in creating a healthier India," Prime Minister has tweeted.
The Prime Minister's Mann ki Baat radio programme is aired on the last Sunday of every month.