Jerusalem (CNN) -- Israel´s Prime Minister Benjamin Netanyahu launched a major review of the country´s defense strategy on Wednesday, as the embattled regional power tries to adapt to a post- Arab Spring world.

Netanyahu took the rare step of summoning the entire Cabinet to discuss the new five-year strategy, his office said.

"We must be ready for the changing threats that are being directed at the State of Israel," he told ministers as the meeting began, according to the statement from his office. "We must see to it that the security which Israelis have enjoyed over past three-and-a-half years continues under the changing conditions."

The toppling of Egypt´s long-time President Hosni Mubarak last year destabilized Israel´s southern border, while the civil war in Syria could affect its northern frontier.

Egypt has been struggling to clamp down on militants in the Sinai desert, which borders Israel.

An increased defense budget is needed to counter new threats all around the country, a former Israel Defense Forces deputy chief of staff said Wednesday.

"The Muslim Brotherhood is forming a ring around Israel, out of Sinai and other places so with all this we need more money for the home front," said the retired officer, Uzi Dayan.

If the Sinai is not demilitarized, it becomes a new front, Dayan said. Syria could become a Sunni Muslim state if secular dictator Bashar al- Assad is forced out, he added.

"If ... weapons from there get into the hands of terror organizations, this is a threat," he said, as is the ongoing possibility of missiles from Lebanon and Gaza.

"In the long run the Americans are leaving Iraq, leaving Afghanistan, so there is new pressure from the east. So these are the new threats - - not to mention the main threat posed by Iran," he said.

The government review will affect the defense budget starting next year, Netanyahu said. It is not expected to be completed in a single day, he added. (© 2012 Cable News Network 08/15/12)