Parts of Israel will effectively shut down starting April 6, rescue officials will conduct mass evacuation exercises and hospitals and even the Knesset will test their ability to operate during a mock chemical and biological weapons attack, The Jerusalem Post said.

Israeli officials familiar with the plans said the drill is in response to lessons learned during the 2006 war with Hezbollah militants in southern Lebanon. It is also to be prepared in case of an Iranian or Syrian nuclear attack on Israel, the Post said.

"This is the biggest exercise in Israel's history," said one official familiar with the planning.

Other officials stressed the exercise isn't based on any imminent threat to Israel.

Emergency officials Tuesday are to conduct a smaller scale emergency exercise at a hospital in Ashkelon.