Chief Justice John Roberts is blaming both parties for the political stalemate that's prevented dozens of federal judicial nominees from filling their seats at the bench. 

In his annual State of the Judiciary report, Roberts said the partisan bickering has led to "acute difficulties" in "critically overworked districts." He urged policymakers to come up with a long-term solution to the perennial problem.

"Each political party has found it easy to turn on a dime from decrying to defending the blocking of judicial nominations, depending on their changing political fortunes," Roberts wrote in the 12-page report. "This has created acute difficulties for some judicial districts. Sitting judges in those districts have been burdened with extraordinary caseloads." 

After months of delay, Senate Republicans this month allowed the approval of 19 of President Obama's 38 pending judicial nominees. Those nominees were considered noncontroversial, but Republicans were blocking them as leverage to prevent votes on other more controversial judges.

Roberts praised the recent movement, but indicated there's much more to be done.

"I am heartened that the Senate recently filled a number of district and circuit court vacancies, including one in the Eastern District of California, one of the most severely burdened districts," Roberts wrote. 

"There remains, however, an urgent need for the political branches to find a long-term solution to this recurring problem." 

Roberts also used the State of the Judiciary report to warn of funding shortages surrounding the nation's courts. 

"We will strive to reduce costs where possible," he said, "but we ask in return that our coordinate branches of government continue to provide the financial resources that the courts must have to carry out their vital mission."