The foreign ministers of Egypt, Jordan, France and Germany on Tuesday jointly stated their vehement opposition to Israel’s plan to unilaterally annex parts of the West Bank, warning that such a move could destabilize the region and would negatively affect bilateral relations with Jerusalem.

“We concur that any annexation of Palestinian territories occupied in 1967 would be a violation of international law and imperil the foundations of the peace process. We would not recognize any changes to the 1967 borders that are not agreed by both parties in the conflict,” Sameh Shoukry, Ayman al-Safadi, Jean-Yves Le Drian and Heiko Maas said in a statement issued after they discussed the matter via videoconference.

“We also concur that such a step would have serious consequences for the security and stability of the region, and would constitute a major obstacle to efforts aimed at achieving a comprehensive and just peace. It could also have consequences for the relationship with Israel,” they added.

The statement marked the first time Cairo formally threatened that annexation could impact its relations with Jerusalem.

Shoukry has spoken out against Prime Minister Benjamin Netanyahu’s plan to apply Israeli sovereignty to all settlements across the West Bank and the strategically important Jordan Valley. But Egypt has so far been notably reserved in its public criticism of the planned move.

By contrast, Jordan, France and Germany have all been affirming for weeks that annexation could not go unchallenged.

“We underline our firm commitment to a negotiated two-state solution based on international law and the relevant UN resolutions. We discussed how to re-start a fruitful engagement between the Israeli and the Palestinian side, and offer our support in facilitating a path to negotiations,” the joint statement concluded.

The Hashemite Kingdom is perhaps the strongest critic of Israel’s annexation plan, with King Abdullah saying it “would lead to a massive conflict” with his country.

Also on Tuesday, al-Safadi held a virtual meeting with senior officials from Oman, Kuwait, Tunisia, Egypt, Morocco and the United Arab Emirates, and the secretary-general of the Arab League, to discuss “the latest developments in the Palestinian question.”

Le Drian last month told French lawmakers that Paris would be prepared to consider punitive measures, especially in the economic and commercial spheres, in response to an Israeli annexation.

Maas, who on June 10 came to Jerusalem to express Berlin’s “serious and honest worries” about annexation, has so far refrained from publicly discussing sanctions, arguing that now is not the time for threats.

On Monday evening, Netanyahu spoke with his UK counterpart Boris Johnson, reiterating his readiness to “conduct negotiations on the basis of [US] President [Donald] Trump’s peace plan, which is both creative and realistic, and will not return to the failed formulas of the past,” according to a readout provided by Netanyahu’s office.

The two leaders agreed to bolster ties between their countries in all fields and in particular to deepen cooperation in the fight against the coronavirus outbreak, the readout said.

According to a readout provided by Number 10, Johnson “set out his concerns” about an Israeli annexation and “cautioned that this would set back the prospects for peace in the region.”

He also urged Netanyahu to return to negotiations with the Palestinians.

Netanyahu has embraced the Trump plan, which has been entirely rejected by the Palestinians.

The prime minister has been pushing to move ahead with a key aspect of the plan that allows Israel to extend sovereignty to its settlements in the West Bank and the Jordan Valley, together comprising about 30% of the West Bank territory. Under the US plan, the remaining 70% would be allocated to the Palestinians for a future state.

Though Netanyahu had set July 1 as a target date to unilaterally apply sovereignty, he has refrained from taking steps amid wide opposition in the international community and even Washington, and among his political allies.

Peace negotiations between Israel and the Palestinians have been moribund since 2014.

In a counter to the Trump plan, the Palestinians last month presented their own proposal and offered to restart direct negotiations on the basis of an Israeli withdrawal to pre-1967 lines, with minor border adjustments.