Mitt Romney's campaign downplayed Donald Trump's surprise endorsement on Thursday, suggesting Romney sees danger in a full embrace of the reality TV star and real estate mogul.

Romney and Trump met briefly in Las Vegas Thursday, where Romney wryly accepted the endorsement. "There are some things you just can't imagine in your life — this is one of them," he said.

His campaign's press release also seemed to deliberately deemphasize Trump. "I am humbled by the endorsements I have received from Republicans across the political spectrum. Donald Trump’s endorsement of me today sends a strong signal that he believes we have the best chance to make President Obama a one-term president," Romney said in a statement. "We share both a background in the private sector and a belief that Washington needs to get out of the way of small business. His support is a sign that business leaders are fed up with Washington and want someone with actual experience creating jobs and working in the real economy in the White House."

The email did not quote Trump at all and below Romney's quote listed dozens of Romney backers, both unusual moves for the campaign.

Trump is popular with some conservatives for his strong attacks on President Obama. But he is dangerous to Romney for a few reasons. His repeated questions on whether Obama is an American citizen and claims that Obama's birth certificate is a "forgery" is out of line with mainstream thinking. Democrats also released a video mocking Trump's signature line, "You're fired," and tying it to Romney's recent gaffes.