"I urge everyone, especially those in affected areas, to get their MMR vaccines to protect their children, families and communities", Mr de Blasio said in the statement.
More than 280 people in Brooklyn and Queens have come down with measles since September.
Some residents - even those who support vaccination - said they felt uncomfortable with the city pushing vaccines on people who did not want them.
"We can not allow this unsafe disease to make a comeback here in New York City".
To date, 285 cases have been confirmed since the beginning of the outbreak in October, with numerous new cases being confirmed in the last two months. While there have been no confirmed deaths so far, 21 people have been taken to hospital, with five admitted to intensive care, officials said.
Parents of children older than six months must get them vaccinated or show proof of immunisation.
Barbot cited a group of "anti-vaxxers" who are seeking to undermine the public health emergency.
"They're spreading this information through hotlines, some publications. We've seen a large increase in the number of people vaccinated in these neighbourhoods, but as Passover approaches, we need to do all we can to ensure more people get the vaccine". "The measles vaccine works".
The outbreak has been predominately among ultra Orthodox Jews, and not unsimilar to outbreaks among other insular communities in recent years where parental fears about immunization have been influenced by an anti-vaccine movement in the larger population that persists despite scientific studies showing the safety of the measles, mumps and rubella vaccine.
The infection can cause serious illness and complication in infants, pregnant women, and those compromised immune systems, she continued.
There are large outbreaks of measles in Europe and Israel, as well as in countries in South America, Africa, and Asia.
The Brooklyn outbreak is part of a broader resurgence in the USA, with 465 cases reported in 19 states so far this year, according to the Centers for Disease Control and Prevention (CDC).
"It's true that a lot of people have measles and measles are not a very good thing, but I think the vaccine also not a very good thing", Williamsburg resident Aron Braver said.
"This is the epicenter of a measles outbreak that is very, very troubling and must be dealt with immediately", de Blasio said, who also assured the public that the vaccine "is safe".
While the MMR vaccine is the safest and most effective method of prevent measles, it is only 97 percent effective, so population-wide immunity is a key component to protecting our most at risk New Yorkers from measles.