Trump says 'somebody is not telling the facts' about Biden cancer diagnosis

President Donald Trump on Monday called former President Joe Biden's cancer diagnosis "very sad" before raising questions about the timing of Biden's public disclosure of the disease.

"I think it's very sad, actually," Trump said while taking questions in the Oval Office. "I'm surprised that it wasn't, you know -- the public wasn't notified a long time ago because to get to stage nine -- that's a long time."

Trump then appeared to try to cast doubt on the doctors in charge of Biden's health during and after his presidency, stating "somebody is not telling the facts."

Biden's office on Sunday said he had been diagnosed on Friday with prostate cancer, saying that while it was "a more aggressive form of the disease, the cancer appears to be hormone-sensitive which allows for effective management."

The statement said Biden's cancer had a "Gleason score of 9." The Gleason grading system, or Gleason score -- which usually ranges from 6 to 10 -- refers to how likely the cancer is to advance and spread, but does not predict the outcome.

During his remarks on Monday, Trump repeatedly referred to Biden's cancer as at "stage nine," rather than the Gleason score. He also seemed to allege that the doctor seeing Biden also might have covered up a mental decline in Biden.

"And it takes a long time to get to that situation. Now, I think, you know, to get to a stage nine, I think that, if you take a look, it's the same doctor that said that Joe was cognitively fine. There was nothing wrong with him. Well, he said -- if it's the same doctor, he said there was nothing wrong there. And that's being proven to be a sad situation," Trump said.

"In other words, there are things going on that the public wasn't informed. And I think somebody is going to have to speak to his doctor if it's the same, or even if it's two separate doctors," he said. "Why wasn't the cognitive ability, why wasn't that discussed? And I think the doctor said he's just fine. And, it's turned out that's not so. It's very dangerous. Look, this is no longer politically correct. This is dangerous for our country," Trump said.

Joe and Jill Biden said on Monday they were thankful for the "love and support" they've received since the former president's office announced his cancer diagnosis on Sunday.

"Cancer touches us all," the couple said in a post on Joe Biden's social media account. "Like so many of you, Jill and I have learned that we are strongest in the broken places. Thank you for lifting us up with love and support."

The post included a photo of the couple, along with their cat, Willow.

Cancer touches us all. Like so many of you, Jill and I have learned that we are strongest in the broken places. Thank you for lifting us up with love and support, the post said.

White House press secretary Karoline Leavitt was asked on Monday if Trump had spoken to Biden directly following Biden's prostate cancer diagnosis.

"Not to my knowledge, I don't believe they have spoken, but I'm sure the president would be open to doing that," Leavitt said. "I spoke to him last night about the former president's cancer diagnosis and the statement that he put out was the initial reaction he had with me on the phone as well."

Trump wrote on his social media platform on Sunday, "Melania and I are saddened to hear about Joe Biden's recent medical diagnosis. We extend our warmest and best wishes to Jill and the family, and we wish Joe a fast and successful recovery."

Biden's cancer diagnosis comes after a small nodule was found in the former president's prostate after "a routine physical exam," a spokesperson said on Tuesday. The discovery of the nodule "necessitated further evaluation," his spokesperson said at the time.

The sentiment in Joe Biden's social media post about being stronger in the "broken places" is derived from a well-worn line in "A Farewell to Arms," a novel by Ernest Hemingway, which says, "The world breaks everyone and afterward many are strong at the broken places." It's a citation that Biden has often applied in difficult and important moments, both in his life and for the general public.

Biden used the phrase in 2016, as he opened his speech at the Democratic National Convention. He then quoted the line in March 2021, as the country marked the first anniversary of the declaration of the COVID-19 pandemic. And he repeated it in September 2021, on the 20th anniversary of the Sept. 11 terror attacks, using Hemingway's words in his tribute to the victims.

ABC News' Averi Harper, Brittany Shepherd, Eric M. Strauss and Leah Sarnoff contributed to this report.