"Tammy and I send our best wishes to President Trump and First Lady Melania Trump for a speedy and complete return to good health," said New Jersey Governor Phil Murphy in a statement. "If there is one thing we have learned in New Jersey over these months, it's that we pull together and support everyone fighting this virus."
Trump made a stop at his golf club in Bedminster, New Jersey Thursday for a fundraiser just hours before he and Melania tested positive.
Murphy also tweeted, "We urge everyone who attended yesterday's event in Bedminster to take full precautions, including self-quarantining and getting tested for #COVID19."
New York Governor Andrew Cuomo, who has been critical of Trump's dismissals of the importance of wearing face coverings, tweeted, "My thoughts are with President Trump and the First Lady and I wish them a full and speedy recovery. This virus is vicious and spreads easily. Wear a mask. Let's all look out for each other."
Later, during a teleconference, Cuomo expressed hopes that the Trumps' symptoms are mild.
"We may disagree on policy issues. But, on a human level, the president grew up in New York, (he's) from Queens. I know the first lady, I've spoken with her, so i sincerely wish them the best for a speedy recovery."
New York City Mayor Bill de Blasio addressed the news during an appearance on a morning radio show.
"I think it's another reminder of why what so many of us have been saying is right: wear masks, practice social distancing, take it seriously," de Blasio said. "Of course this president didn't do that, unfortunately, and we all pay the price. Look, I wish him a speedy recovery for the good of all. But it is clear that people need to follow this guidance for everyone to be safe. This is just the object lesson of it."
WATCH: Former NJ Gov. Chris Christie comments on Trump's COVID diagnosis
Fmr. NJ Governor Chris Christie talks about Trump's COVID diagnosis
Former New Jersey Governor Chris Christie said he was tested while prepping President Trump earlier this week for the debate with Joe Biden, and that his result was negative.
"I was at the White House from Saturday afternoon through lunch Tuesday, on and off during those days. I was tested every day. The last test I took was Tuesday morning," Christie said.
He told ABC's Good Morning America that he feels fine but was planning to get another test Friday morning.
"No one was wearing masks in the room when we were prepping the president during that period of time," Christie said. "The group was about five or six people in total."
Asked if he noticed any symptoms in the president, Christie said no.
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