The war between Israel and Hamas in Gaza is increasingly having an effect on neighboring Jordan.

"The country is very involved in the war across the border," Kelly Petillo, Middle East researcher at the European Council on Foreign Relations, or ECFR, told DW.

"More than halfof Jordan's population is of Palestinian origins, Queen Rania herself has Palestinian roots and the issue of Palestinian statehood sees huge support from the population and the government," she said.

In turn, Jordan's King Abdullah II has sharpened his tone against Israel since the beginning of the war that was prompted by the deadly Hamas attack on Israel on October 7. During the Cairo Summit for Peace in late October, Abdullah II called Israel's siege and bombardment of Gaza "a war crime."

Since then, bilateral relations between the two countries that signed a peace treaty in 1994 and collaborate closely across economic, energy and security related projects, have reached a new record low.

Both ambassadors were recalled in early November.

This week, the Jordanian king said that "there is no victory in the carnage that has been unfolding" in an opinion piece published by the Washington Post newspaper.

However, at the same time Abdullah II has been calling for a return to the two-state-solution that would grant Palestinians their own state with East Jerusalem as capital. Abdullah also drafted the resolution for a cease-fire which was adopted by the UN General Assembly last month.

"No one will prevail unless the Palestinians are given their rights and their state. Only this will be a true victory for peace, for Palestinians and for Israelis alike. And that, more than anything, would be a victory for our common humanity," he wrote in the op-ed.

Solidarity in Jordan, but no border crossing

Yet, when it comes to taking in Palestinians either from Gaza or from the Occupied West Bank, King Abdullah II remains steadfast, similar to Egypt which also rejects the thought to host Gazans in the Sinai Peninsula.

Since October 7, Abdullah II has repeatedly said that there will be no new Palestinian refugees in Jordan, declaring this a red line that should not be crossed.

"Domestically, resources are overstretched, and accepting Palestinian refugees would mean being complicit in killing the Palestinian cause," Petillo told DW.

This view is echoed by Edmund Ratka, the head of the German Konrad Adenauer Stiftung Foundation Office Jordan.

"For decades, Jordan's strategic nightmare scenario has always been a renewed wave of expulsion of Palestinians across the River Jordan into Jordan," he told DW, adding that "everyone in Jordan wants to avoid that at all costs."

In his view, this includes "the Jordanians of Palestinian origin because they want the Palestinians to live in self-determination in Palestine, which means west of the River Jordan."

However, he points out that it also applies to the long-established Transjordanian tribes in Jordan, "because they are worried that the demographic and thus also the power-political balance of the country could be upset and the old Transjordanian tribes will become even more of a demographic minority," he said.

According to United Nations data, the Jordanian population totaled 11,355,133 in the first week of November.

Various sources estimate that around half of the population is of Palestinian origin as Jordan is the only Arab country that has been granting citizenship to Palestinians who came in 1948 during the Nakba — which translates to "catastrophe" in Arabic and refers to the Palestinians who lost their homeland during and after the Arab-Israeli war in 1948 — and to those who entered Jordan after the six-day-war in 1967.

Also, more than two million people remain registered as Palestinian refugeesin Jordan, according to the United Nations Relief and Works Agency for Palestine Refugees in the Near East.

Increasing domestic anger in Jordan

Alongside the opposition to taking in more Palestinians in Jordan, solidarity with Palestinians and Gazans has reached a new high. "We have daily demonstrations, public mourning or vigils and in almost every coffee shop you have solidarity stickers for Palestine, Palestinian flags and Palestinian scarves," Ratka, who lives in Amman, said.

"The Jordanians are angry at the situation but they are also helpless in a way and one of the means they use is boycott," Ratka said. For example, Starbucks and McDonald's, which are outlets of Israel's ally America, are empty, even though the local branches are in Jordanian hands.

"That might not have a big economic impact but it shows the high level of mobilization within the society," Ratka observed.

A potentially more dangerous aspect of the growing public sentiment is the increased support for the Hamas militant group, which is identified as terrorist organization by the EU, the US, Germany and many other countries.

"Traditionally, Hamas has never had broad support in Jordan, and certainly not at government level, but now we are seeing that radical Islamist voices are gaining a hearing on the street and on social media in Jordan," Ratka said.

In turn, the Jordanian government has started arresting dozens of protesters in the past two weeks.

"We are seeing a certain escalation, which goes hand in hand with the escalation of the conflict and the ever-increasing suffering of Palestinian civilians in Gaza," Ratka added.

Furthermore, protesters have started calling for an end of the peace treaty with Israel.

"I don't think the overall agreement will collapse easily," the ECFR's Kelly Petillo said, adding "particularly in light of Jordan's close relationship with the United States."

According to the US Department of State, the US is Jordan's single largest provider of bilateral assistance, providing more than $1.65 billion (€1.47 billion) in 2021, as well as also around $1.7 billion (€1.57 billion) in humanitarian assistance to support Syrian refugees. Furthermore, at least 3,000 US troops are based in Jordan.

Backlash against Israel-Jordan projects

However, as unlikely as an end of the peace treaty seems at the moment, Edmund Ratka thinks other cooperation projects with Israel will be negatively affected as a consequence of the strained relations.

"The best example is this 'Water for Energy Deal' which was agreed on in November 2021 together with the United Arab Emirates," he said.

The trilateral deal outlined that a solar power plant in Jordan would provide green electricity for an Israeli desalination plant, which would in return supply much needed desalinated water to Jordan.

"It is not possible to communicate such a project, which is still in the planning phase, to the public anymore," Ratka said.

On Thursday, Jordanian Foreign Minister Ayman Safadi announced that the deal had been halted for the time being.