Calls for calm and de-escalation amid persistent Israeli air strikes emerged from around the world, while others urged "both sides" to exercise restraint.
Calls have grown for a de-escalation of violence after Israeli air strikes on Gaza that have left at least 65 dead, including 16 children, and hundreds injured.
The Israeli army has launched hundreds of air strikes on the Palestinian enclave since Monday, while Palestinian groups launched more than 1,000 rockets in some of the worst violence in seven years.
At least six people have died in Israel since the start of Israeli military action, one of them a soldier hit by a missile fired from Gaza.
Tensions have been running high since an Israeli court ordered the eviction of Palestinian families from the Sheikh Jarrah neighbourhood of occupied East Jerusalem.
Some countries have urged peaceful de-escalation while others voiced support for the warring parties under "self defence".
Powers calling on Israel to de-escalate
President Vladimir Putin urged Israelis and the Palestinians to halt fighting in a call with Turkish counterpart Recep Tayyip Erdogan, who said the world needed to give Israel a "strong" lesson.
"Serious concern was expressed about the continuing clashes and the growing number of people killed and wounded," the Kremlin said in a statement.
Putin had "called on the parties to de-escalate tensions and peacefully resolve the emerging issues", the statement added.
Erdogan told Putin the international community needed to "teach a deterrent lesson" to Israel, adding that Ankara was working to mobilise this reaction, according to a statement from his office.
Erdogan said nations should also discuss the "idea of sending an international protection force to the region in order to protect Palestinian civilians".
"UN Security Council should get involved, give clear messages to Israel to halt attacks before crisis grows further," Erdogan added.
Erdogan, a vocal advocate of the Palestinian cause, has stepped up diplomacy, speaking to a range of regional leaders and condemning Israel's "terror".
The chief prosecutor of the International Criminal Court expressed concern that "crimes" might have been committed.
"I note with great concern the escalation of violence in the West Bank, including East Jerusalem, as well as in and around Gaza, and the possible commission of crimes under the Rome Statute," which founded the ICC, Fatou Bensouda said on Twitter on Wednesday.
The Organisation of Islamic Cooperation (OIC) condemned Israel and reiterated support for Palestinians.
The pan-Islamic body based in the Saudi city of Jeddah said it "condemns in the strongest terms the repeated attacks by the Israeli occupation authorities against the Palestinian people", in a statement.
It also denounced "the Israeli occupation forces' continuation of their colonial programmes – building settlements, attempting to confiscate Palestinian properties, forceful eviction of Palestinians from their land."
Jordan and Saudi Arabia called for effective international efforts to protect Palestinians against Israeli attacks and violations.
The call came during talks over the phone between Jordanian Foreign Minister Ayman Safadi and his Saudi counterpart Prince Faisal bin Farhan.
The statement said the two ministers condemned "illegal Israeli practices", warning that continued Israeli aggression against the Al Aqsa Mosque and Gaza, and the eviction of Palestinian families from their homes in the Sheikh Jarrah neighbourhood will have consequences.
The UN relief agency for Palestinian refugees condemned “in the strongest possible terms" the killing of four children the previous day in an Israeli air strike on Gaza.
UNRWA says the children – two siblings and two cousins – were killed near the refugee camp of Beit Hanoun. It says they were under the age of 12 and went to schools in the territory sponsored by the agency.
"Isreal has a right to defend itself": Powers calling on both sides to exercise restraint
Some countries called on "both sides" to cease hostilities, creating a false equivalency when viewing the exchange of fire between Israeli troops and Hamas.
British Prime Minister Boris Johnson urged Israelis and the Palestinians to "step back from the brink", calling for both sides to "show restraint".
"The UK is deeply concerned by the growing violence and civilian casualties and we want to see an urgent de-escalation of tensions," he said on Twitter.
The United States urged both Israelis and the Palestinians to avoid "deeply lamentable" civilian deaths, calling for "calm" after days of violence.
US President Joe Biden said that Israel has a right to defend itself after speaking with Prime Minister Benjamin Netanyahu and said he hopes the violence will end soon.
"I had a conversation with Bibi Netanyahu not too long ago," Biden told reporters. "My expectation and hope is that this will be closing down sooner than later, but Israel has a right to defend itself when you have thousands of rockets flying into your territory."
"Israel does have a right to defend itself. At the same time reports of civilian deaths are something that we regret and would like to come to a stop," State Department spokesman Ned Price said.
"We don't want to see provocations. The provocations we have seen have resulted in a deeply lamentable loss of life," he said.
US Defense Secretary Lloyd Austin reiterated the United States' "ironclad support" for Israel's right to defend itself in a call with his Israeli counterpart, the Pentagon said.
The European Union's foreign policy chief called for an immediate end to the violence in Israel.
"Everything must be done to prevent a broader conflict, which will, first and foremost, affect the civilian populations on both sides," Josep Borrell said in a statement.
Italy and Germany want an immediate end to the violence between Israelis and Palestinian groups, Italian Foreign Minister Luigi Di Maio said after talks with his German counterpart.
"We strongly request all the parties to immediately take measures aimed at de-escalation and to exercise the greatest restraint," De Maio said in a statement.
China's special envoy on the Middle East, Zhai Jun, expressed "deep concern" and urged all parties to exercise restraint to avoid further casualties.
In a meeting with Arab envoys and the chief representative of the Arab League in China, Zhai said Beijing would continue to push the UN Security Council to take action on the situation in East Jerusalem as soon as possible, according to a foreign ministry statement.