There is a great concern about what is happening in Egypt, one senior diplomatic official said. We are following very closely the events and are analyzing them as they occur.

The officials said they expect Mubarak to survive the unrest but that it could damage ties with Israel if the country's popular opposition group, the Muslim Brotherhood, makes gains.

Egypt was the first Arab country to reach peace with Israel three decades ago. It remains one of Israel's most important allies by acting as a bridge to the wider Arab world.

It is experiencing the fiercest anti-government protests in years, threatening to destabilize Mubarak's regime.

The Israeli security officials, also speaking on condition of anonymity, said they were worried that violence might spread to Gaza, the West Bank, and possibly to its other ally in the Arab world, Jordan.