UN Secretary-General Ban Ki-moon has called on Israel to end its military operation in Gaza immediately.
In a phone conversation with Prime Minister Ehud Olmert Saturday evening, Ban conveyed his "extreme concern and disappointment" over the launching of the IDF's ground incursion and said he was "convinced and alarmed that this escalation will inevitably increase the already heavy suffering of the affected civilian populations."
According to Ban's spokesman, the UN chief "reiterated his call for an immediate cessation of all violence, and urged regional and international partners to exert all possible influence to bring about an immediate end to the bloodshed and suffering."
The UN Security Council scheduled emergency consultations Saturday night to address the escalation of violence in Gaza. The decision to hold consultations came after Israeli tanks and infantry rolled into Gaza in a ground offensive in a widening war against Hamas.
Meanwhile, the US State Department issued a statement saying it was working toward a ceasefire between Israel and the armed Palestinian groups in the Hamas-controlled territory that would bring an end to the continued rocket fire on the Jewish state.
Cautious statements from the State Department and the White House voiced concern about the humanitarian situation in Gaza, but did not directly criticize Israel for moving ground forces into Gaza.
State Department spokesman Sean McCormack said "it's obvious the ceasefire should take place as soon as possible," but it has to be sustainable and cannot allow Hamas to continue to launch rockets out of Gaza.
'Diplomatic window is open'
The US has asked the Israeli government to be mindful of potential consequences of its actions to civilians, McCormack said, noting that the US is deeply concerned about the humanitarian situation in Gaza.
The French Foreign Ministry condemned the IDF's ground incursion and the continued rocket fire emanating from the Strip, while British Foreign Secretary David Miliband said Israel's ground offensive into Gaza shows the urgent need for an immediate ceasefire and warned that military escalation will cause "alarm and dismay".
Also Saturday, Spanish Foreign Minister Miguel Moratinos called Palestinian president Mahmoud Abbas to express his "support and solidarity" after Israel launched the ground incursion.
Olmert and Foreign Minister Tzipi Livni have set up a task force, headed by PM aide Shalom Turgeman, to address the growing international pressure and provide the IDF with ample time to complete its mission.
Russian Foreign Minister Sergei Lavrov, French President French Nicolas Sarkozy and his Foreign Minister Bernard Kouchner are expected to arrive in Israel on Sunday to head the diplomatic efforts to end the conflict.
An official in Jerusalem said, "Currently there is no diplomatic initiative that addresses Israel's demand to cease all terror activities in Gaza and put an end to the strengthening of the Hamas regime there.
"The diplomatic window is open, but in the meantime the IDF will carry out the cabinet's orders to continue operating on the ground," he said.
Israel is also demanding that a truce agreement include the establishment of an international supervising body in Gaza.
Roni Sofer and AP, AFP contributed to the report