(CNN) Sen. Rand Paul said he plans to filibuster the reauthorization of Section 702 of the Federal Intelligence Surveillance Act (FISA) if necessary, as the House prepares to vote on a six-year extension of the program.

Section 702, which allows the intelligence community to monitor foreign communications, is set to expire January 19. Critics of the program argue that it allows the warrantless collection of US citizens' private information.

"My worry is that they also collect information on millions of Americans, and I don't want that database to be searched without a warrant," the Kentucky Republican said.

He added, "I will filibuster and do whatever to stop that."

Paul said he would vote to reauthorize Section 702, however, if there are protections in place for Americans' private information, and added that he supports the USA Rights Act, another amendment to the program proposed by Rep. Justin Amash, R-Michigan.

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