[WASHINGTON] President Barack Obama on Friday called for Donald Trump's White House bid - and his past record - to be held to close scrutiny as he warned the US presidency was not a "reality show."
With Mr Trump seizing the mantle of presumptive Republican nominee this week after his rivals dropped out of the race, debate has turned to whether the provocative billionaire will be able to rally party faithful behind him between now and November.
Asked about Mr Trump's candidacy, and the resulting chaos on the Republican side, Democrat Obama offered some of his most pointed comments yet about the celebrity real estate mogul and long-time star of TV show "The Apprentice," whose political rise has stunned the world.
"We are in serious times and this is a really serious job," Mr Obama told reporters at the White House. "This is not entertainment. This is not a reality show." "What that means is that every candidate, every nominee needs to be subject to exacting standards and genuine scrutiny."
Mr Trump has raised howls of protest even within his party with his harsh, free-wheeling speech and proposals ranging from banning Muslims from entering the United States to building a wall on the southern border to keep out Mexican migrants to slashing US funding for NATO so allies have to pay more.
"He has a long record that needs to be examined, and I think it's important for us to take seriously the statements he's made in the past," Mr Obama said.
The presidential words of warning came a day after the nation's top elected Republican official, House Speaker Paul Ryan, refused to publicly support the presumptive nominee and said Mr Trump has "some work to do" to win over skeptics within his camp.
In a possible olive branch, Mr Ryan invited Mr Trump to meet with him and fellow party leaders in the House next Thursday to discuss "the kind of Republican principles and ideas that can win the support of the American people this November."
But Mr Ryan's warning to Mr Trump threw the Grand Old Party deeper into soul searching over how to mount a viable campaign to win the likely matchup with Democrat Hillary Clinton in November.
Several party elders - including the last two Republican presidents, George W Bush and George H W Bush - have refused outright to endorse Mr Trump.
Senator Lindsey Graham, himself a former 2016 presidential candidate, became the latest establishment Republican to opt out, announcing Friday that he would not vote for him or Mrs Clinton.
Mr Graham said on Twitter he does "not believe he is a reliable GOP conservative nor has he displayed the judgment and temperament to serve as commander in chief."
Instead, Mr Graham said he will focus on a goal many other Republicans have highlighted as a necessity for November: helping Republicans maintain their majorities in the House and Senate.
Mr Trump said he was taken aback by Ryan's rebuke.
"And it's fine. He can do whatever he wants to do. But I was surprised by it," Mr Trump told Fox News.
Mr Ryan, the 2012 Republican vice presidential nominee, has stressed the burden was on Mr Trump to begin the healing process within his fractured party.
But Mr Trump's clumsy effort to reach out to one alienated group of voters triggered an immediate backlash Thursday after he tweeted a photograph of himself eating a taco bowl, adding "I love Hispanics!"
"Honestly, he's trying," Republican National Committee chairman Reince Priebus, who has urged conservatives to back Mr Trump, said Friday.
"I honestly think he understands that building and unifying and growing the party is the only way we're going to win." Democrats, buoyed by polls which show Mrs Clinton leading Mr Trump head-to-head, seized on the Trump-Ryan clash to highlight the GOP turmoil.
"Mr Trump has gone radioactive," Democratic National Committee spokesman Mark Paustenbach said.
Mrs Clinton, who leads a resilient Bernie Sanders in their Democratic nomination battle but has yet to seal the deal, has already pivoted to Mr Trump, calling him a "loose cannon" and saying Americans cannot risk electing him commander in chief.
Some conservatives, including Senator Ben Sasse of Nebraska, argue that a third candidate should challenge Mr Trump and Mrs Clinton.
"Why are we confined to these two terrible options?" Mr Sasse asked in an open letter. "If both choices stink, we reject them and go bigger."
Speaking on the Republicans' Mr Trump conundrum, Mr Obama said its voters will ultimately have to "make a decision as to whether this is the guy who speaks for them and represents their values." "I'll leave it up to the Republicans to figure out how they square their circle."