CAIRO (AP) — Egypt’s main opposition alliance called for a “No” vote in the referendum on a disputed constitution rather than a boycott, hours after Islamist President Mohammed Morsi’s government forged ahead by starting overseas voting in diplomatic missions for expatriates.

The opposition’s decision did not dispel the atmosphere of a nation in crisis, deeply polarized over the referendum that has stoked three weeks of turmoil on the streets. The opposition still plans more protests and the country’s judges are still on strike over a decree by Morsi, since rescinded, that placed him above judicial oversight. The military is inching back into politics. And if the referendum passes, there is potential for even greater upheaval.