TEL AVIV—As deaths from airstrikes on the Gaza Strip passed 100 and rockets continued to rain into Israel, Prime Minister Benjamin Netanyahu said international pressure wouldn't influence his assault against Hamas and all options were possible, including a ground invasion.
Sirens on Friday wailed through Israel's major cities warning of incoming rockets, and the country's military said it exchanged fire with Lebanon in an area believed to be controlled by the militant group Hezbollah.
Meanwhile, Hamas militants, who have been launching hundreds of missiles into Israel from the Gaza Strip, vowed to press on with their fight and said they will attack the Tel Aviv airport, telling airlines not to land their planes there.
Officials in Washington said that with little momentum behind a swift diplomatic deal to end the attacks, chances of an Israeli ground operation appeared to be growing. "It's going to get worse before it gets better," said one senior U.S. military official.
Asked in a news conference on Friday if Israel planned to invade, Mr. Netanyahu told reporters: "We're preparing for all options."
Mr. Netanyahu said he had spoken recently with his counterparts from the U.S., Germany, France and Russia, among others, to explain Israel's operation against Hamas.
But he added: "No international pressure will prevent us from operating with full force against a terrorist organization that calls for our destruction."
Israel on Friday mobilized some 30,000 reservists who could move into Gaza at a moment's notice, Israel Defense Forces spokeswoman Libby Weiss said.
On Friday, U.S. Defense Secretary Chuck Hagel called his Israeli counterpart, Moshe Ya'alon, to express "concern about the risk of further escalation" and urge "all sides to do everything they can to protect the lives of civilians and restore calm,"
Some Pics Captured in Phalestine.
Phalestine are Praying for the Peace
Mr. Amidror warned that an operation to uproot Hamas house-by-house in Gaza wouldn't be quick. He estimates it took two years for Israel to end Hamas' influence in the West Bank after a reinvasion of the territory in the early 2000s. The Palestinian Authority also has limited influence in Gaza, meaning its 1.7 million people could become Israel's responsibility.
Mr. Oren, who wrote a book about Israel's victory in the 1967 war, agreed. "There are no more Six Day War moments anymore," he said.