Seven Republican presidential candidates will participate in Fox Business Network's prime-time debate on Thursday, but Senator Rand Paul of Kentucky and former business executive Carly Fiorina did not qualify for the main event, the network said on Monday.

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The seven candidates chosen for the main debate by Fox Business, based on the network's polling criteria, were billionaire businessman Donald Trump, Texas Senator Ted Cruz, Florida Senator Marco Rubio, retired neurosurgeon Ben Carson, New Jersey Governor Chris Christie, former Florida Governor Jeb Bush and Ohio Governor John Kasich.

Fiorina, former Arkansas Governor Mike Huckabee and former Pennsylvania Senator Rick Santorum will participate in the so-called undercard debate for low-polling candidates earlier in the evening, the network said. Paul told CNN he will not take part in the undercard debate.