Citing a threat to Israeli democracy, opponents of Prime Minister Benjamin Netanyahu asked the Supreme Court on Sunday to block what they described as a power grab by the caretaker government under the guise of combating the coronavirus epidemic.

The petitioners asked the court to restore the full powers of Parliament, which has been largely blocked from functioning by a Netanyahu ally, Yuli Edelstein, the speaker. He has claimed public health concerns.

A new Parliament was sworn in last week, but among the key votes Mr. Edelstein has prevented is one on replacing him as speaker.

The paralysis in Parliament has only compounded the country’s political deadlock and chaos in the wake of three inconclusive elections in the past 12 months.