Donald Trump said he is postponing the press conference scheduled for Friday morning where he was set to announce his vice presidential pick.
Trump and his campaign team have made repeated announcements this week that he would be formally announcing the name of his vice presidential pick on Friday, at the end of a week of detailed speculation over who he would choose.
Earlier today, Trump asked Mike Pence to be his running mate, and the Indiana governor accepted, a source with direct knowledge tells ABC News.
Trump gave a phone interview on Fox News shortly after posting the tweet and explained his reaction to the Nice attack.
"Well, it sounds like here we go again," Trump said.
"It's going to be a whole different world. We're living in a whole different world. There is no respect for law and order. There is no respect for anything or anybody."
Later he was asked about his vice presidential pick, denying that a decision has been made and praising his top three candidates: Pence, New Jersey Gov. Chris Christie and former Speaker of the House Newt Gingrich.
"I haven't made a final, final decision," he said.
Trump called Fox News a second time and said that the news conference was cancelled because he thought it would be "inappropriate" given the attack in France. Trump told Bill O'Reilly that he'll "be making the announcement at the appropriate time."
ABC News confirms that Pence was seen landing at an airport near New York City this afternoon.