Israel threatened to escalate its attacks on the Hamas-controlled Gaza Strip on Sunday, positioning tanks and armoured personnel carriers close to the border and calling up 6,700 reservists for a possible incursion into the territory, the Financial Times reported.
Israel said that the offensive, aimed at security services and government headquarters, was designed to stop the recent surge in rocket and mortar fire from Gaza-based militants on nearby Israeli towns. One Israeli was killed and several more wounded by rocket fire on Saturday, as Hamas bombarded Israeli targets throughout the weekend.
Khaled Meshal, political leader of Hamas who lives in exile in Damascus, urged Palestinians to launch a third intifada against Israel, in a reference to uprisings in 1987 and 2000. He told a television station that Hamas's response would include suicide bombings inside Israel.
Tzipi Livni, Israel's foreign minister and leader of the governing Kadima party, rejected international appeals to halt the attacks, and urged governments to support Israel. "I don't accept these calls. Hamas is a terror organisation and Israel is a country that is defending its citizens. The only possible way to cut the offensive short is to make it clear that Israel has the right to protect itself and that the international community backs Israel."
Ms Livni, one of the frontrunners to succeed Ehud Olmert as prime minister after elections on February 10, stressed that Israel had no intention of reoccupying the strip. However, other senior government officials made it clear that the country was ready to send in ground troops.
Ehud Barak, defence minister, told a US television station that "if boots on the ground will be needed, they will be there".
The Israeli air force on Sunday also bombed more than 40 tunnels linking Gaza and Egypt, which officials said were used for smuggling weapons and explosives. Two Palestinians were reportedly killed in the strikes.
Also on Sunday the United Nations Security Council issued a unanimous statement voicing concern for the situation and calling for an immediate halt to all violence. It echoed statements from world leaders calling for calm and for a renewal of the ceasefire agreed in June between Israel and Hamas.
There were protests and demonstrations against the offensive throughout the Arab world, as well as in several European capitals. In the occupied West Bank as well as in Israel, Palestinian demonstrators clashed repeatedly with Israeli forces. One protester was killed.
However, some voices in the Arab world indicated that Hamas bore some responsibility. Mahmoud Abbas, Palestinian president and head of Fatah - Hamas's rival - said: "We talked to them [Hamas] and told them 'please, we ask you, do not end the truce. Let the truce continue and not stop' so that we could have avoided what happened."
The US administration, Israel's closest ally, blamed the recent escalation on Hamas alone, saying that Israel had the right to defend itself against what George W. Bush's National Security Council called "thugs".
It was not clear how many of the casualties in Gaza were civilians. The Reuters news agency quoted a Hamas official saying that there were 15 women and children among the dead.