Nour Odeh, Al Jazeera's correspondent in neighbouring Jordan, said: "This is probably one of the most violent Israeli air campaigns against Gaza."
"Politically speaking, this is devastating... We can see people in Ramallah coming out on the streets, calling on the leaderships in the Palestinian territories to unite, and set aside their differences knowing that that will be difficult, as it has been for the past year and a half.
"It will certainly be very embarrassing for Mahmoud Abbas [the Palestinian president], who is engaged in a peace process with Israel, trying to convince a very sceptical public that a political process with Israel can yield results while these bombs are raining on Gaza."
Yasser Abed, an adviser to Abbas speaking in the West Bank said: "In this moment we express our solidarity with all the victims of this aggression.
"And we call for an immediate halt and ending of this aggression against the Gaza Strip.
"Our leadership and our government are taking measures now in order to help the victims of the aggression"
Spokesman for Mahmoud Abbas, Palestinian president
"Our leadership and our government are taking measures now in order to help the victims of the aggression."
Abbas said he was in "urgent contact" with numerous countries over the raids.
Angry demonstrations also broke out in Oum el-Fahem, Nazareth, Sahnin and Tamra in northern Israel in response to a call from leaders of the country's Arab community.
Protesters chanted slogans condemning "Israeli aggression" and waved Palestinian flags.
The Israeli bombardment sparked rallies across the Arab world, including in Amman, the capital of Jordan, and Damascus in Syria.
"It's a Zionist holocaust, but it won't dissuade us from going on with our struggle to achieve our goals," Ali Barakah, one of the protesters at al-Yarmouk camp, outside Damascus, said.
In Beirut, Palestinian and Lebanese protesters gathered outside the Egyptian embassy, calling on Egypt to open the Rafah crossing into the Gaza Strip.
Protesters held candles and Palestinian flags, chanting pro-Hamas and anti-Israel slogans.