ABC's Shushannah Walshe and Emily Friedman report:

So, what exactly is Mitt Romney doing on Thursday? Is he dining with The Donald or will Trump have to dine alone?

It's all a bit of a mystery as Donald Trump's camp is saying The Dine with Donald Raffle winner- whose identity is not known - will dine with Romney and Trump tomorrow. The meal will be held at The Pierre at the private residence of stock investor and financial analyst Martin Zweig.

Later on Thursday night, Romney has a $50,000 a head fundraiser at the same residence at The Pierre Hotel in Manhattan.

But, that's not what the Romney camp is saying. They actually aren't saying much, not commenting on the Thursday events to ABC, although Trump took to Twitter to promote the events. The event is a fundraising raffle where small-dollar donors from all over the country got a chance to enter to win and have dinner with Trump and the presumptive GOP nominee.

It's the same day the Supreme Court will rule on the constitutionality of the president's health care legislation.

On Tuesday, Trump tweeted, "Looking forward to the "Dine with Mitt and Donald" this Thursday. Can't wait to meet the lucky winner. @MittRomney"

Romney aides did not respond to questions from ABC News as to whether the meal with Trump and the winner is happening Thursday.

Could it be the Romney campaign has realized Trump may hurt more than he helps?

Get more pure politics at ABC News.com/Politics and a lighter take on the news at OTUSNews.com

The two last appeared together in May at a fundraiser in Las Vegas. It was the day before Romney racked up enough delegates to become the party's presumptive nominee, but it was overshadowed by the reality show and real estate tycoon's comments about President Obama's citizenship.

Trump belongs to the "birther" movement, which despite being thoroughly debunked, believes the president was not born in this country and therefore is not a "natural born citizen" as required by the Constitution to be president of the United States.

Though the president releasing his birth certificate last April, they still question its legitimacy. The president was born in Hawaii and the state has even re-affirmed that fact.

While in Las Vegas, just hours before the fundraiser at the Trump International Hotel in Las Vegas, Trump told CNN, "A lot of people do not think it was an authentic certificate."

Romney has said he believes the president was born in this country, but has refused to criticize Trump's incorrect claims only saying the day before the Las Vegas fundraiser, "I don't agree with all the people who support me. And my guess is they don't all agree with everything I believe in."