LAS VEGAS - On the very day that Donald Trump's birther comments have dominated coverage of the presidential race, Mitt Romney managed to slip in a reference during a speech to the U.S. birth requirement for anyone who wants to be president.

"I was speaking with one of these business owners who owns a couple of restaurants in town," said Romney at a campaign event here in Las Vegas, mentioning a private roundtable he held ahead of the event with local residents. "And he said you know I'd like to change the constitution."

"I'd like to have a provision in the constitution that in addition to the age of the president and the citizenship of the president and the birthplace of the president being set by the constitution, I'd like it also to say that the president has to spend at least three years working in business before he could become President of the United States," said Romney, recalling the businessowner's suggestion.

Then Romney seemed to agree with the suggestion.

"You see then he or she would understand that the policies they're putting in place have to encourage small business, make it easier for business to grow," said Romney.

Romney is on his way to a fundraiser at Trump's hotel here in Las Vegas. Trump has spent the day standing by his assertion that there is no actual proof that President Obama was born in the United States.

Earlier this week, Romney did not outright condone Trump's suggestion, telling reporters that he does not agree with everything his supporters say and vice versa.