MILWAUKEE — Former President Trump has decided on his running mate, and it won't be Sen. Marco Rubio of Florida or North Dakota Gov. Doug Burgum.

Multiple sources told Fox News on Monday that Rubio - the three-term conservative senator who was considered to be among the names on a short list of contenders for running mate - was informed that he wouldn't be named as the GOP's 2024 vice presidential nominee.

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Sen. Marco Rubio of Florida is considered a front-runner for Trump's running mate

Sen. Marco Rubio, R-Fla., arrives to speak before Republican presidential candidate former President Donald Trump at a campaign rally at Trump National Doral Miami, Tuesday, July 9, 2024, in Doral, Fla.  (AP Photo/Rebecca Blackwell)

And sources also told Fox News that Burgum, the two-term North Dakota governor and top Trump surrogate, was also informed that he would not be named as the former president's running mate.

The Trump campaign says that the first time we will see the running mate in-person will be at the Fiserv Forum in Milwaukee, where the Republican National Convention kicked off on Monday, at 4:37PM ET, just ahead of the vice presidential roll call nominating process. 

Burgum and Trump together campaigning

Former President Donald Trump arrives to speak at a caucus night rally in Las Vegas, Feb. 8, 2024, as North Dakota Gov. Doug Burgum watches.  (AP Photo/Alex Brandon, File)

Besides Rubio and Burgum, Sen. JD Vance of Ohio was also considered to be a front-runner to serve as Trump's running mate.

Get the latest updates from the 2024 campaign trail, exclusive interviews and more at our Fox News Digital election hub.