Angela Rayner is pressing Sir Keir Starmer to follow Emmanuel Macron and formally recognise a Palestinian state.
The Deputy Prime Minister is understood to be “100 per cent” behind other Cabinet ministers pressuring the Prime Minister over the decision.
A third of Labour MPs signed a letter on Friday saying it was time for “immediate recognition”.
It comes after Emmanuel Macron, the French president, pledged to recognise Palestine as a state at the next UN General Assembly in September.
The Labour Government backs Palestinian statehood but has argued for months that it should be formally recognised at the right moment to further peace in the region.
However, there is growing pressure in the party for a change to be made sooner.