Barack Obama
Barack ObamaReuters

President Barack Obama on Tuesday offered a full-throated endorsement of Hillary Clinton’s fitness to serve as president while blasting Donald Trump as unfit to be president, The Hill reports.

“You want to debate who’s more fit to be our president?” Obama asked a Philadelphia crowd during a solo campaign appearance for Clinton.

“We have one candidate who’s traveled to more countries than any secretary of State ever has, has more qualifications than pretty much anyone who has ever run for this job,” he continued.

Obama said that Republican nominee Donald Trump, by comparison, “isn’t fit in any way shape or form to represent this country abroad and be its commander in chief.”

The president also defended Clinton’s stamina to serve in the nation’s highest office, which her critics have questioned after her pneumonia diagnosis was revealed on Sunday.

“She worked hard, tirelessly flying around the world again and again,” said Obama, according to The Hill. “I don’t know how many times she lapped the world but she did it a long time.”

The comments come two days after Clinton was abruptly removed from a 9/11 memorial event in Manhattan when she suffered what senior law enforcement officials described as a “medical episode.”

Clinton's doctor later revealed that she was suffering from pneumonia and the incident at the memorial was a result of dehydration and overheating.

The Clinton campaign has come under fire for saying originally that Clinton was just “overheated” and not revealing until later she had been diagnosed with pneumonia the prior Friday.

The campaign acknowledged that it mishandled her health scare and promised to release additional medical details in the coming days

Obama, in his remarks Tuesday, also bemoaned the media coverage of transparency issues that he said has been too favorable to Trump, ripping him for refusing to release his tax returns like other past presidential nominees.

"You want to debate transparency?" he asked. "You've got one candidate in this race who's released decades worth of her tax returns. The other candidate is the first in decades who refuses to release any at all."

With Clinton recuperating at home, Obama sought to reset the tenor of the debate with a forceful, energetic speech that lavished praise on his preferred successor.

“I am really into electing Hillary Clinton,” he told the crowd, which numbered more than 6,000, according to the Clinton campaign. “This is not me going through the motions here. I really, really, really wanna elect Hillary Clinton.”

The president dismissed the Republican nominee’s effort to position himself as a working-class hero.

“Really, this is the guy you want to be championing working people?” he asked, according to The Hill. “This guy, who spent the first 70 years of his life showing no concern for working people?

“I mean, he wasn’t going to let you on his golf course,” he added. “He wasn’t going to let you buy in his condo. And now suddenly this guy is going to be your champion?”

Obama then mocked Trump’s praise for strongmen like Russian President Vladimir Putin.

“He loves this guy,” he said. “Think about the fact that that is Donald Trump's role model. I have to do business with Putin, I have to do business with Russia. That's part of foreign policy, but I don't go around saying that's my role model.”

Obama is seeking to fire up voters in the Keystone State, a traditional Democratic stronghold where the race between Clinton and Trump has narrowed in recent weeks.

A Quinnipiac University poll released last week showed Clinton holding only a five-lead over her Republican opponent there.