Prime Minister Andy Burnham has added his name to a letter condemning the proposed expansion of illegal Israeli settlements in the occupied West Bank.
The letter, signed by a number of international leaders, urges the Israeli government to abandon the plan, warning that it would undermine prospects for a two-state solution.
Settlements built on land occupied by Israel since 1967 are considered illegal under international law by most countries, a position Israel disputes.
“Joint statements matter because they show Israel that opposition to settlement expansion is broad and coordinated.”
Critics of the proposed expansion say it would further fragment Palestinian territory and make the creation of a viable Palestinian state increasingly difficult.
“The UK's position is clear: settlement expansion is illegal and an obstacle to peace,” a government spokesperson said.
Israeli officials have defended settlement activity in the past, citing historical and security grounds, and have rejected international criticism as interference.
Palestinian leaders welcomed the international statement but called for practical measures to accompany words of condemnation.
The letter comes amid wider international concern over the situation in the region, with diplomats pressing for renewed efforts towards a lasting political settlement.
The settlement issue has been a long-standing point of contention in efforts to resolve the Israeli-Palestinian conflict, with successive peace initiatives stalling amid disagreements over borders, security and the future of Jerusalem.
It is not yet clear whether the Israeli government will proceed with the plan, which still requires further approvals before construction can begin.
