Donald Trump said "something's going on" with Hillary Clinton's health, but had little else to say about Clinton's collapse in New York other than to hope she's all right.

"I really just don't know," the Republican presidential nominee said on "Fox and Friends" in a phone interview on Monday morning. "I hope she gets well soon. I don't know what's going on."

Trump, who has said repeatedly that Clinton isn't healthy enough to run for president, speculated that last week's coughing fit in Ohio may have been pneumonia.

"I see what I see. The coughing fit was a week ago, so I assume that was pneumonia also," Trump said. "I mean, I would think it would have been. So, something's going on, but I just hope she gets well and gets back on the trail and we'll be seeing her at the debate."

The results of Trump's own recent physical examination will be released soon, he said.

"I'll be releasing, when the numbers come, hopefully they are going to be good, I think they are going to be good, I feel great, but when the numbers come in, I'll be releasing very, very specific numbers," Trump remarked.

During a 9/11 memorial ceremony, Clinton was seen stumbling as she left the event early. Her campaign initially said she was "overheated" before later revealing she had been diagnosed on Friday with pneumonia. The Democratic nominee's two-day California trip scheduled for Monday was postponed.