ISTANBUL — In a signal that Turkey faces indefinite rule by decree, President Recep Tayyip Erdogan announced on Sunday that a state of emergency, introduced as a temporary measure after last year’s failed coup, would continue until the country achieved “welfare and peace.”

The state of emergency allows Mr. Erdogan and his cabinet to issue sweeping decrees without parliamentary oversight or review by the constitutional court, giving him an almost untrammeled grip on power.

So far, the decrees have allowed Mr. Erdogan to jail more than 40,000 people accused of plotting a failed coup, fire or suspend more than 140,000 additional people, shut down about 1,500 civil groups, arrest at least 120 journalists and close more than 150 news media outlets.

In late April, a decree issued under the state of emergency was used to block access to Wikipedia.

Despite international criticism of these measures, Mr. Erdogan said on Sunday that the state of emergency “will not be lifted,” according to Anadolu Agency, a state-owned news wire. “Until when? Until the situation reaches welfare and peace.”