Officials of the Morsi government have indicated that they prefer to wait until the election of a new Parliament, which might demonstrate broader public agreement on the need for changes. But a court decision striking down the election law has postponed the vote until at least the fall, and many economists say Egypt cannot endure the delay.

“The situation is pretty urgent, because the deterioration accelerates,” a Western diplomat said, speaking on the condition of anonymity under diplomatic protocols. Shortages, the diplomat said, are already leading to layoffs.

Energy subsidies make up as much as 30 percent of Egypt’s government spending, said Ragui Assaad, of the Economic Research Forum here. The country imports much of its fuel, and for the first time last year it was forced to import some of the natural gas used to generate electricity — the reason for the recent blackouts. Egypt also imports about 75 percent of its wheat, mixing the superior foreign wheat with lower-quality domestic supplies to improve its subsidized bread.

But the two years of mayhem in the streets since the ouster of Mr. Mubarak have decimated tourism and foreign investment, crippling the economy. The government’s reserve of hard currency has fallen to about $13 billion from $36 billion two years ago.

About half of its currency reserves are in illiquid forms like gold, economists say, while billions more are owed to the foreign companies that operate Egypt’s oil and gas fields. And as a result of the outflows of hard currency, the value of the Egyptian pound has also been falling.

Diesel fuel is the crux of the crisis, in part because Egypt has a very limited capacity to refine it. Diesel is also essential to much of the economy. Not only do farmers use it to power machinery for irrigation and harvesting, diesel truck fuel contributes to the price of almost everything shipped.