"We are going to guarantee health care for New Yorkers who need it," De Blasio told MSNBC. "We now have in New York City something that we can build on; we have a public [health care] option that we are ready to make much bigger".
The mayor specified that the plan would cover about 600,000 uninsured residents in the city, a number that includes illegal immigrants.
Health care has become a major political issue in the US, with Republicans lifting restrictions that have made many policies under a national system known as Obamacare unaffordable and prominent Democrats advocating a government-run national health system to replace Obamacare.
The mayor added that participants will also be told how to get care from a specialist, such as an obstetrician/gynaecologist or mental health provider. De Blasio also said he will hold a press conference later on Tuesday to explain his plan in greater detail.