Republicans are vowing to press ahead with confirmation hearings this week for Donald Trump’s Cabinet nominees despite the concerns of a federal watchdog that their complex backgrounds are slowing required ethics reviews.

Senate Majority Leader Mitch McConnell (R-Ky.) said Sunday that there are no plans to alter a packed confirmation calendar, but he vowed that no nominee will earn an up-or-down vote until the requisite background checks are completed by the FBI and a federal ethics office.

“The Democrats are really frustrated that they lost the election,” he told CBS’s “Face the Nation,” adding that he was in a similar situation eight years ago when President Obama took office.

“What did we do? We confirmed seven Cabinet appointments the day President Obama was sworn in. We didn’t like most of them, either. But he won the election,” McConnell said. “So all of these little procedural complaints are related to their frustration at having not only lost the White House, but having lost the Senate. I understand that. But we need to, sort of, grow up here and get past that.”

McConnell was responding to concerns expressed by Walter M. Shaub Jr., director of the Office of Government Ethics, who said in a letter released Friday that the current confirmation calendar is putting “undue pressure” on his office to “rush through these important reviews.”

(Bastien Inzaurralde/The Washington Post)

Shaub, appointed in 2013 to lead the executive branch’s ethics office, warned that there are some unresolved ethics issues for nominees set to appear on Capitol Hill this week, adding that he was unaware of any Cabinet pick sitting for a confirmation hearing before completing an OGE review.

[Ethics official warns against confirmations before reviews are complete]

But Senate Republicans strongly disputed Shaub, noting that at least some hearings have been held before the OGE completed reviewing a nominee’s past.

Take the Senate Health, Education, Labor and Pensions Committee, for example. The panel requires a nominee to complete a questionnaire — part of which is released publicly, while a portion containing personal information remains private. The committee also requires that a nominee undergo an ethics review by the OGE and an FBI criminal background check.

In January 2001, the committee held a confirmation hearing for Roderick Paige, George W. Bush’s choice to lead the Education Department, eight days before the OGE completed its review, aides said. That month, the committee met with Elaine Chao, tapped to serve as Bush’s labor secretary, five days before the OGE sent its findings to Capitol Hill.

[Trump’s nominees]

This year, Chao, who is also McConnell’s wife, is nominated to serve as Trump’s transportation secretary, and her ethics and FBI background checks have been completed ahead of her hearing, scheduled for Wednesday with the Senate Commerce Committee, aides said. Her hearing will occur amid a flurry of other televised meetings with Trump nominees, including attorney general pick Sen. Jeff Sessions (R-Ala.), set to meet with the Judiciary Committee on Tuesday, and secretary of state pick Rex Tillerson, set to appear before the Foreign Relations Committee on Wednesday.

Elaine Chao, Trump’s choice to serve as transportation secretary, photographed on Nov. 21, 2016, at Trump Tower in New York. (Carolyn Kaster/AP)

All of Sessions’s paperwork is completed, including the FBI background check, according to Senate aides. Tillerson turned in his ethics report a few days after being nominated but is awaiting the results of an FBI check, said those aides, who are not authorized to speak publicly about the reviews.

Betsy DeVos, Trump’s choice for education secretary, has yet to submit her ethics report, but her FBI check is completed ahead of her Wednesday hearing with the Senate Health, Education, Labor and Pensions Committee, aides said. Paperwork for retired Marine Gen. John Kelly, nominee to lead the Department of Homeland Security, also has been completed ahead of his Wednesday hearing.

On Thursday, the Senate Banking Committee will meet with Ben Carson, Trump’s choice to lead the Department of Housing and Urban Development, while the Senate Commerce Committee will meet with Wilbur Ross, Trump’s choice to lead the Commerce Department. Both nominees are still undergoing ethics and FBI reviews, aides said.

[Everything you want to know about the Trump Cabinet confirmation hearings]

Senate Minority Leader Charles E. Schumer (D-N.Y.) on Sunday again faulted Republicans for the confirmation schedule.

“No administration, Republican or Democrat, has tried to do what these Republicans are trying to do with their nominees,” Schumer said in a statement. “Rather than ensuring that nominees are thoroughly vetted and will remove themselves from conflicts of interests, Senate Republicans are trying to ram them through as quickly as possible.”

He added: “Until these nominees have fully cooperated with the ethics review process, the hearings and confirmation schedule should not be rushed.”

A former general counsel and acting director of the Office of Government Ethics, Don W. Fox, said his former agency should not be faulted for slowing down the confirmation of Trump’s Cabinet.

“I would not fault OGE at all” for this circumstance, he said. “There is no lack of sophistication there among the staff on complex financial arrangements. But it is a small agency, and the laws are exacting.”

As a result, cooperation and communication with the agency are required, Fox said. Given the number of wealthy nominees and reports of a lack of communication between the ethics office and Trump’s team, “it’s not surprising that this is where we are,” he added.

Tom Hamburger contributed to this report.