Yachad, the British organisation that advocates a two-state solution, has urged the UK Government to reject Donald Trump’s “one-sided” Middle East peace plan, which promises to keep Jerusalem as Israel's undivided capital.

Mr Trump’s plan, which proposes an independent Palestinian state, includes US recognition of Israeli annexation of settlements in the occupied West Bank.

Yachad said in a statement: "Annexation will not only destroy any chance of a viable Palestinian state, it will also risk Israel’s hard-won peace with Jordan, widely acknowledged as one of Israel’s most important strategic assets."

The group said it was “alarmed” that Prime Minister Boris Johnson has already welcomed this deal in dialogue with the Mr Trump.

It comes after a Downing Street spokesperson said the leaders had “discussed the United States’ proposal for peace between Israelis and Palestinians, which could prove a positive step forwards."

“President Trump's one-sided ‘Deal of the Century’ is a recipe for perpetual occupation and conflict and must be rejected," a spokesperson for Yachad said, adding Israeli Prime Minister Benjamin Netanyahu had "said he considers this deal to be a US endorsement of his dangerous plan to annex settlements and much of the West Bank.

“Annexation will not only destroy any chance of a viable Palestinian state, it will also risk Israel’s hard-won peace with Jordan, widely acknowledged as one of Israel’s most important strategic assets.

“We call on the UK government to reject this one-sided plan. It is not pro-Israel to overlook the needs and rights of Palestinians when doing so will perpetuate the conflict.

"If the UK is truly interested in seeing peace in the region, it should renew its efforts in the fight for real peace between two independent states living side by side.”

Standing alongside Mr Netanyahu at the White House on Tuesday, Mr Trump said his proposals "could be the last opportunity" for Palestinians.

Mahmoud Abbas, president of the Palestinian Authority, rejected the plans as a "conspiracy."

Speaking in a televised address from Ramallah in the West Bank, he said: "I say to Trump and Netanyahu: Jerusalem is not for sale, all our rights are not for sale and are not for bargain. And your deal, the conspiracy, will not pass.”

The New Israel Fund UK echoed the concerns of Yachad, saying the recognition of Israeli annexation of settlements “hands Israel’s future to the radical settler right.”

NIF chief executive Adam Ognall said: “The Trump Administration is offering Israeli officials and the radical settler right a free pass to march in the opposite direction: toward a future of unending injustice and inequality.

“This plan threatens to make the occupation permanent. If it becomes reality, there will be no two-state solution.

“This will cripple Israeli democracy by putting Israel in permanent control over the lives of millions of Palestinians who will have no right to vote for their own future. This is not the vision of Israel’s founders. It is not the vision of those of us who love and care about the state of Israel.”

Mr Ognall said the decision facing Israelis remains the same as it was in 1967 and they “must choose between Israel’s Jewish character, its democracy, and its control over the Palestinian territories.

“Israel can choose two, but not all three. No unbalanced presidential edict disguised as a ‘peace plan’ will obscure this choice and no Israeli government will escape it.”

Israeli protest movement Peace Now, which also advocates a two-state solution, also condemned Trump's plan describing it as “detached from reality.”

In a statement, it said: “The plan’s green light for Israel to annex the settlements in exchange for a perforated Palestinian state is unviable and would not bring stability.”

The group said that any outline for peace that does not include the “establishment of a Palestinian state on the basis of the pre-1967 lines with minor land swaps, the evacuation of deep settlements and two capitals in Jerusalem will find its way into the dustbin of history.”

The Zionist Federation of the UK warned that outright rejection of the plan would “not help the Palestinian people”.

It said: “We applaud all efforts to bring peace. We wholeheartedly urge all parties to come to the table to talk. Outright rejection will not help the Palestinian people.”

Board of Deputies President Marie van der Zyl said the organisation remains committed to a two-state solution, leading to a secure Israel alongside a viable Palestinian state.

She said: "We would ask the two sides to find ways around their differences and work towards a future that allows for the flourishing of both peoples.”