WASHINGTON — A House GOP push to permanently extend expiring provisions of the Patriot Act is running into opposition from conservative and tea party-inspired lawmakers who are wary of the post-Sept. 11 law’s reach into private affairs.

Civil libertarians have long fought the George W. Bush-era law that makes it easier for federal authorities to conduct surveillance on suspected terrorists, often drawing support from Democratic allies in Congress.

But as the Republican-led House prepares to vote today for a short-term extension of provisions that expire at the end of this month, rank-and-file Republicans are signaling they will resist efforts later this year to make the law permanent.

“There need to be sunsets on the bill after that in order to have adequate accountability and oversight,” said Rep. Louie Gohmert, R-Texas. “Until sunsets come up, it is often difficult to get the answers we need to do necessary oversight to avoid abuses from someone tempted to be overzealous.”

Rep. Jason Chaffetz, a Republican in tea party-strong Utah, said he has not yet decided how he will vote today.

Tea party adherents prefer a smaller federal government, creating common cause on this issue with civil libertarians who object to expanded surveillance powers for federal authorities in the aftermath of the 2001 terrorist attacks.

The three most contested provisions of the Patriot Act expire on Feb. 28, and the White House has worked with congressional leaders to secure an extension through December 2013. The Democratic-led Senate is considering legislation to do so.

The House GOP, though, is seeking to pass a shorter extension, to Dec. 8, 2011, to give lawmakers in that chamber time to assess making the provisions permanent.

Rep. Jim Sensenbrenner, R-Wis., the author of the original bill, is seeking the permanent extension.

“I fully understand the intense legal scrutiny these provisions have undergone over the last several years and support making them permanent,” said Sensenbrenner, the chairman of the Judiciary subcommittee on crime, terrorism and homeland security. “These three provisions have helped thwart countless potential attacks since the bill was signed into law and are critical to helping ensure law officials can keep our nation safe from attack.”

The three provisions up for renewal have long raised objections from civil libertarians, including the so-called “library” provision that allows federal investigators, with a judge’s approval, to access a wide cache of a suspect’s personal materials — including library records.

Another expiring provision allows the government to conduct court-approved roving wiretaps of suspected terrorists as they change phones or locations. A third is the “lone-wolf” provision that enables authorities to conduct surveillance on foreign terrorism suspects who do not appear to be affiliated with known groups.

The Obama administration supports the 2013 extension of the expiring provisions, but has disappointed civil libertarians who have pushed for a greater overhaul of the law.

“Our goal for 10 years has been to rein in these authorities and limit their use to suspected terrorists and spies,” said Michelle Richardson, legislative counsel for the ACLU. “It’s very unlikely if these provisions are made permanent they’ll never get the review necessary to maintain privacy.”