WATCH LIVE: Senators Rand Paul and Ron Wyden filibuster the Patriot Act
Senator Ron Wyden (Screenshot)

Republican U.S. Senator Rand Paul began giving a speech on Wednesday to oppose any vote on legislation that would extend U.S. spy agencies' collection of Americans' telephone data.

Under Senate rules, Paul, a 2016 presidential candidate, can stay on the Senate floor and speak without interruption until midnight, when the next legislative day begins.

Republicans, who control both the Senate and House of Representatives, have been unable to agree on how to deal with the June 1 expiration of provisions of the USA Patriot Act used to justify the collection of billions of telephone call records.

The House voted 338-88 last week to approve the USA Freedom Act, which would end bulk data collection and replace it with a system of targeted information retrieval.

But that bill has yet to come up for a vote in the Senate, where Majority Leader Mitch McConnell and other lawmakers said they favored renewing a program they say is essential to securing the safety of Americans.

McConnell said on Tuesday the Senate has "an obligation" to address the expiration of the Patriot Act provisions and would deal with it this week. He also said he would allow a vote on the USA Freedom Act.

Watch live video, courtesy of NBC News, below: