NEW YORK - Mayor Bill de Blasio is acknowledging flaws in the city's snow response after initially defending all of its cleanup efforts.

The mayor backtracked Wednesday night following criticism that plowing fell behind on Manhattan's upper east side. He had said during a news conference following the snowstorm that all neighborhoods and boroughs were treated equally, and commended the Department of Sanitation for its work.

However, after visiting the area, he released a statement saying, "I determined that more could have been done to serve the upper east side." He added that more crews were sent there to finish cleanup, and that he still felt the overall response was "well-executed."

De Blasio also defended the decision to keep the public school system open after the city was hit with about a foot of snow. He said that it was important to only close schools when absolutely necessary.