Grassley called it the "Thurmond-Leahy" rule, after former Sen. Strom Thurmond and current Judiciary Committee Chairman Pat Leahy (D-Vt.). He also rejected the idea that Republicans should not invoke this rule because they have not confirmed enough judicial nominations for the Obama administration.

"Since 2008, the Senate has confirmed 149 circuit and district court judges and two Supreme Court Justices nominated by President Obama, and his term is not over," he said. "During President Bush's entire second term, which was the last time two Supreme Court Justices were confirmed, the Senate confirmed a total of only 119 circuit and district court judges."

He also said the Senate confirmed a similar number of circuit court nominees as was confirmed for President George W. Bush, and even more district court nominees.

"Based on this record, it's disingenuous to suggest that Senate Republicans have not been fair in the consideration and confirmation of judicial nominees," he said. "And, it is entirely appropriate and consistent with past practice to invoke the Thurmond-Leahy rule at this point."

Earlier Thursday, Leahy said he would keep pressing to allow votes for circuit court judges, and accused Republicans of obstructionism.

"It is hard to see how this new 'Thurmond Rule' shutdown is anything more than another name for the stalling tactics we have seen for months and years," he said.

The GOP decision came just two days after Grassley demanded that the Senate vote again on the nomination of Andrew Hurwitz to serve in the 9th Circuit. Grassley said he was not aware Democrats would voice-vote Hurwitz, and said he never agreed to yield debate time in order to hold the vote Tuesday.