CAIRO: A credit rating downgrade on Monday and an opposition challenge to a constitutional referendum, which the ruling Islamists said that they won added to Egypt’s political crisis and piled pressure on President Mohamed Morsi.

Morsi’s Muslim Brotherhood said that its numbers show 64 percent of voters backed the new charter, despite weeks of protests by the secular-leaning opposition.

But the electoral commission said that it was investigating opposition allegations of fraud during the two-stage referendum held on December 15 and 22.

Official results would not be released until the commission could show the voting “really reflects the will of the Egyptian people,” commission official Mohamed el-Tanobly told Agence France-Presse.

The National Salvation Front opposition coalition warned that, regardless of the outcome, “the referendum is not the end of the road. It is only one battle.”

That raised the prospect of more protests like the ones confronted, which have Morsi for more than a month, leaving the Arab world’s most populous nation polarized and its political institutions paralyzed.

Clashes on December 5 outside Morsi’s Cairo Palace killed eight people and wounded hundreds, prompting the army to deploy troops and tanks.

Rating agency Standard and Poor’s on Monday downgraded Egypt’s long-term credit rating one notch to ‘B-’ and said that it could be cut further if foreign exchange reserves or the government’s deficit sharply worsen.

“We expect political tensions to remain elevated, with no clear indication that rival factions will be brought to a point at which they can contribute to addressing Egypt’s economic, fiscal, and external challenges,” the agency said.

Agreement on a $4.8-billion loan from the International Monetary Fund was put on hold this month, accentuating the risk of Egypt’s currency collapsing.

The central bank has run through more than half its foreign reserves since the ouster of longtime president Hosni Mubarak early last year, leaving less than $15 billion.

Egypt’s economy, once a vibrant opportunity for investors, was brought low by the 2011 revolution and has continued to lag under Morsi.

It was unclear how a political remedy could be reached.

Morsi and the Muslim Brotherhood are using their newfound power to spearhead rapid changes they contend will put Egypt on the path to stability.