(CNN) House Judiciary Chairman Jerry Nadler, a high-profile Democrat, appeared to nearly faint during a news conference Friday, halting the event as New York Mayor Bill de Blasio offered him assistance.

In the brief episode, Nadler is seen on video appearing disoriented and slow to respond as de Blasio offers him water. Nadler was immediately assisted by medical staff who were at the event, and Nadler responded to them.

Nadler aide Daniel Schwartz told CNN that the congressman "is OK" and that he "seems to have been dehydrated and it was very warm in the room. He is now responsive and receiving a check-up."

Nadler himself later tweeted, that he appreciated "everyone's concern."

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