United Nations Secretary-General Antonio Guterres has condemned Israel’s controversial plan to annex much of the occupied West Bank, saying the move will shut the door on possible “peace negotiations” with the Palestinians.

Guterres made the remarks in a recent meeting with the Arab Group delegation, including Oman, the Arab League and Palestinian officials, denouncing Israeli settlements and the looming annexation plan as illegal.

He noted that the annexation proposal will “effectively end the [so-called] two-state solution and close the door on Israeli-Palestinian negotiations.”

The Arab Group, for its part, slammed the “illegality of all colonization and annexation measures by Israel in Occupied Palestine.”

The group’s delegates emphasized that Israel’s “actions are severely violating the Palestinian people’s rights and destroying the viability of the [so-called] two-state solution on the pre-1967 borders.”

If not stopped, Israel’s illegal actions will bring “only more conflict and suffering” and impede “prospects for peace and security in the entire region,” the group pointed out.