The UAE Minister of State for Foreign Affairs, Dr Anwar Gargash, on Monday said any move by Israel to annex parts of the occupied West Bank would be a serious setback for the Middle East peace process.
Israeli Prime Minister Benjamin Netanyahu has said Cabinet discussions would begin next month on his plan to extend Israeli sovereignty to territory Palestinians want for their own state.
"Continued Israeli talk of annexing Palestinian lands must stop," Dr Gargash said on Twitter.
"Any unilateral Israeli move will be a serious setback for the peace process, undermine Palestinian self-determination and constitute a rejection of the international and Arab consensus towards stability and peace."
Israel has moved forward with plans for annexation after the formation of a new unity government and the unveiling of US President Donald Trump's pro-Israel peace plan this year.
The Palestinians have rejected the plan, which diverts from previous US policy and a 2002 Arab League-endorsed initiative that offered Israel normal relations in return for an independent Palestinian state and full Israeli withdrawal from territory captured in the 1967 Arab-Israeli war.
Palestinian President Mahmoud Abbas said last month he was cutting all ties with Israel and the US, including security co-operation, over Israel's plans to annex the Jordan Valley and Jewish settlements.
The UAE last month criticised Israel's plans at an emergency Arab League session.
The annexation plan "is a dangerous development that would undermine international efforts to resolve the Arab-Israeli conflict", state news agency Wam reported the UAE as saying.
Israel's action is "unacceptable, violates international law and impedes the peace process", it said.
The UAE warned of "dangerous repercussions" and said the move could "fuel extremism, and terrorism in the region".
Arab League Secretary General Ahmed Aboul Gheit accused Israel of “taking advantage of the global preoccupation with confronting the coronavirus epidemic to impose a new reality on the ground”.
On Sunday, the UN's Middle East envoy, Nickolay Mladenov, warned that unilateral action by either side would "most likely trigger conflict and instability" in the region.
The report was released ahead of a meeting this week of international donor nations that support the Palestinian Authority, the internationally recognised entity that governs autonomous areas of the occupied West Bank.
In the report to donors, Mr Mladenov said the coronavirus crisis underscored that the economic status quo was unsustainable.
"All sides must do their part in the coming weeks and months in order to preserve the prospect of a negotiated two-state resolution to the conflict," he said.