The current fighting between Israel and Gaza has the potential to end with more death and destruction than past conflicts, says the former head of the United Nations' Jerusalem office.
David Shearer said it's also a "fantasy" the two-state solution promoted by many world leaders is even close to becoming a reality, with Israel deploying "disproportionate" force.
Five nights of clashes between the bitter enemies have seen at least 132 Gazans killed, Reuters reported, more than 50 of them women and children. Hundreds more have been injured.
On the other side, eight Israelis have died - six of them civilians, including two children.
"The US has said to Israel, look, try and back off, and Israel said, 'No, we're not ready yet,'" Shearer told Newshub Nation on Saturday.
"So it does seem that it's going down a well, certainly for the next few days anyway, it's going to be going down a more perilous path."
Reuters staff on the ground said there appeared to be no end in sight to the warring. It began on Monday (local time) when Hamas launched rocket attacks on Israel, after Israeli refused to withdraw its security forces from the al-Aqsa mosque in Jerusalem, there to put an end to days of clashes.
Hamas, which has ruled Gaza since 2007, had given Israel until 6pm that evening to withdraw. When the deadline passed, the rockets started flying.
As is typical in clashes between Israel and Palestinians, the former responded with great force, using artillery and air strikes to attack targets in Gaza.
Shearer, whose work with the UN was interrupted by a brief foray into politics a decade ago, said Hamas has improved its rocket technology since the last full-scale war in 2014.
"There's some important points to make on what is different between now and 2014. I mean, we had the same sort of episodes happening then. What we're seeing now, though, is Hamas being able to reach places in Israel with their rockets that they were not able to do seven years ago. So they've really developed their rocket technology.
"In addition to that, we're seeing Palestinian Israelis - and remember that Israel is made up of 20 percent Arab. Those Arabs and the Israeli Jews are clashing in towns where they were very mixed. And at the same time, more disruption today on the West Bank where, again, Palestinians are demonstrating. So it's escalated more and dangerously across a wider range of issues than it has done in 2014."
One of those issues is Israel's plan to evict families from the East Jerusalem neighbourhood of Sheikh Jarrah to make way for Jewish settlers. Jews lived in the area for a long time before the Battle for Jerusalem in 1948, after which Palestinian refugees moved in, and they've been the majority there ever since.
"It's undermining and causing this extraordinary tension. East Jerusalem and has always been seen as the part the part of Jerusalem is going to be the the capital of a Palestinian state. And the settlers keep on undermining that by buying up areas of land, in East Jerusalem, in addition to the massive amount of settlement activity that's taking place in the West Bank.
"When I was there a decade ago, there were 450,000 Israeli Jews living in Jerusalem and in the West Bank. Today that's 650,000, so it's gone up to 100,000. You start to question how you can have a two-state solution when that state is going to have 650,000 Israelis living in it. It's starting to be it's starting to feel like it's not going to happen."
Shearer has recently been heading-up the UN's peacekeeping mission in South Sudan.