Sen. Marco Rubio (R-Fla.) will deliver what his office is calling a "major speech on the future of U.S. foreign policy" on Wednesday.

According to Rubio's office, his speech, at the Brookings Institution, a non-partisan think tank, will "focus on whether U.S. global leadership is sustainable and even necessary in the 21st century."


Even though Rubio has tried to make foreign policy one of his signature areas of expertise, the speech will likely add to speculation that Rubio is a strong contender for the VP spot on the GOP presidential ticket. 

On Sunday, Rubio said he would "respect the process," which was a different from his earlier comments where he denied interest in the No. 2 spot.

And Rubio accidentally added to the speculation that he expects to be on the ticket when, during an interview with National Journal, he said he'd have the opportunity to do "all sorts of things" if he does "a good job as vice president."

"If I do a good job as a vice president — I'm sorry, as senator — I'll have the chance to do all sorts of things," Rubio said.

In late March Rubio endorsed Romney for president. He began campaigning with Romney on Monday, the same day the Florida senator's office announced the speech.