Morocco and Israel have agreed to “full diplomatic relations” in a US-brokered deal under which Washington recognises Moroccan sovereignty over the disputed territory of Western Sahara.

“Another historic breakthrough today!” US president Donald Trump wrote on Twitter. “Our two great friends Israel and the Kingdom of Morocco have agreed to full diplomatic relations — a massive breakthrough for peace in the Middle East!”Mr Trump’s administration previously announced similar deals between Israel and the United Arab Emirates, Bahrain and Sudan, a significant shift in regional relations between the Jewish state and Arab nations that threatens to leave the Palestinians with dwindling support.

For Palestinians, the deal is a departing blow from a hostile US president who has overturned decades of American foreign policy in favour of Israel, pushing Gulf states to discard the 2002 Arab Peace Initiative and normalise relations with Israel despite a stalled peace process with the Palestinians.US secretary of state Mike Pompeo and top Trump aide Jared Kushner have also been putting pressure on Saudi Arabia to normalise ties, but the Gulf kingdom has expressed caution.

Benjamin Netanyahu, Israel’s prime minister, welcomed the announcement as “another great light of peace”, saying there would be direct flights between the countries and the opening of diplomatic missions, according to Reuters news agency.

Mr Kushner said Morocco was a “tolerant society” whose leaders had been good to Jewish people in the past, but that “for whatever reason, diplomatic relations did not exist” until now.

The recognition of Moroccan sovereignty over Western Sahara is a break from international norms. The north African country has controlled most of Western Sahara, a disputed desert territory, since 1975 when Spain, the occupying colonial power, withdrew its forces.

Since then the Polisario Front, an Algeria-backed movement, has been seeking independence for the territory. The UN has been trying to organise a referendum on self-determination, which has been stalled for decades.

US recognition of Morocco’s sovereignty over the territory will strengthen its position. Polisario last month announced it was abandoning a ceasefire that ended 16 years of fighting with Morocco in 1991.

Sidi Omar, the UN representative of the Polisario Front, wrote on Twitter that the US decision “shows that Morocco’s regime is willing to sell its soul to maintain its illegal occupation of parts of Western Sahara”.

The US decision will drive another foreign policy wedge between Washington and the EU, which regards Western Sahara as a non-self governing territory and backs a UN process to determine its final status.

“The position of the EU on the Western Sahara dispute remains fully aligned with that of the UN Security Council and its resolutions on Western Sahara,” the EU said. It declined to comment specifically on the Trump administration’s move.

Mr Trump took the decision to recognise Western Sahara as Moroccan territory because of strong trading and intelligence ties between Washington and Rabat, and because there had been “no progress on a resolution” on the issue, Mr Kushner said.

But Robert Malley, former senior Obama official, said the terms of the deal would strike many as “unseemly”. “It is the height of transactional diplomacy, in which an issue as important as relations with Israel is being used as a bargaining chip in pursuit of wholly unrelated goals,” he said, adding it was unclear how the Polisario and Algeria would react.

Judd Devermont, who was national intelligence officer for Africa during the Obama administration, added: “As one of the persistent faultlines in regional integration and co-operation, the United States is trampling over African equities for a short-term win for its Israel policy.”

Mr Devermont, now Africa director at the Center for Strategic and International Studies, said the US decision to recognise Morocco’s sovereignty over Western Sahara would “pose an immediate problem for many African countries” and the African Union, the continent-wide body that also recognises the Polisario-run Sahrawi Arab Democratic Republic, which controls a part of the territory.

Both Morocco and SADR are members of the African Union. “The US decision will increase pressure on the region’s member states to choose sides,” he said.

Morocco has long had informal ties with Israel, and the kingdom has a small Jewish community that it takes pride in protecting. André Azoulay, a Moroccan Jew, is a long-serving adviser to King Mohammed VI and to his father King Hassan II before him.

Jim Inhofe, a Republican who is chairman of the Senate armed services committee, broke with Mr Trump by calling the decision to recognise Moroccan sovereignty over Western Sahara “shocking and deeply disappointing”.

“I am saddened that the rights of the Western Saharan people have been traded away,” said Mr Inhofe, who has campaigned on the issue for years.

Additional reporting by Michael Peel in Brussels and Mehul Srivastava