Sir Keir Starmer is expected to announce the UK's recognition of a Palestinian state in a statement on Sunday afternoon.
The move comes after the prime minister said in July the UK would shift its position in September unless Israel met conditions including agreeing to a ceasefire in Gaza and committing to a long-term sustainable peace deal that delivers a two-state solution.
It represents a major change in British foreign policy after successive governments said recognition should come as part of a peace process and at a time of maximum impact.
The move has drawn fierce criticism from the Israeli government, hostage families and some Conservatives.
Israeli Prime Minister Benjamin Netanyahu previously said such a move "rewards terror".
