Washington (CNN) -- President Barack Obama has sidestepped Congress by using a recess appointment to make Dr. Donald Berwick the new head of the federal agency overseeing Medicare and Medicaid, the White House announced Wednesday.
According to a blog entry posted Tuesday by White House Communications Director Dan Pfeiffer, Republicans in Congress had indicated they would stall Berwick's nomination, made in April, to be administrator of the Centers for Medicare and Medicaid Services.
The recess appointment allows Obama to install Berwick while the Senate is not in session, to serve for the rest of the congressional term, which expires at the end of the year.
Obama also used recess appointments to install a new director of the Pension Benefit Guaranty Corporation and a new associate director at the president's office of Science and Technology Policy.
"It's unfortunate that at a time when our nation is facing enormous challenges, many in Congress have decided to delay critical nominations for political purposes," Obama said in a written statement.
"With more than 180 nominees still pending before the Senate, it's my hope that my colleagues in Congress will agree to put politics aside and move forward on these vitally important positions."
Pfeiffer's blog post noted that the center is overseeing how Medicare and Medicaid -- the government health insurance systems for senior citizens and low-income Americans -- will incorporate the new health care reform bill passed by Congress and signed by Obama earlier this year. The agency has been without a permanent administrator since 2006, the blog post said.
Senate Minority Leader Mitch McConnell blasted Obama's decision in a statement released Tuesday.
"As if shoving a trillion-dollar government takeover of health care down the throat of a disapproving American public wasn't enough, apparently the Obama administration intends to arrogantly circumvent the American people yet again by recess appointing one of the most prominent advocates of rationed health care to implement their national plan," he said.
"Democrats haven't scheduled so much as a committee hearing for Donald Berwick, but the mere possibility of allowing the American people the opportunity to hear what he intends to do with their health care is evidently reason enough for this administration to sneak him through without public scrutiny."
Senate Finance Committee Chairman Max Baucus, D-Montana, also criticized the recess appointment.
"I'm troubled that, rather than going through the standard nomination process, Dr. Berwick was recess appointed," Baucus said Wednesday. "Senate confirmation of presidential appointees is an essential process prescribed by the Constitution that serves as a check on executive power ... and all Americans by ensuring that crucial questions are asked of the nominee -- and answered."
But another top Democrat, Massachusetts Sen. John Kerry, defended the appointment. Kerry attacked the Republicans, arguing in a statement that the GOP's "lockstep stalling of Don's nomination was a case study in cynicism and one awful example of how not to govern."
White House Press Secretary Robert Gibbs later asserted that the appointment was necessary in part because key provisions in the recently passed health care reform law will need to be enacted next year.
"We need somebody on the job now," Gibbs told reporters at the White House. "The president is going to install people that need to be installed for this government to function effectively and efficiently."
Berwick is "uniquely qualified" and the confirmation process is "badly broken," Gibbs added. "The Republican Party had no intention of moving this nomination forward."
Berwick is the founder of the Institute for Healthcare Improvement and has spent decades as a practicing physician and a Harvard professor, according to the White House.
CNN's Alan Silverleib, Ted Barrett, and Deirdre Walsh contributed to this report