Rishi Sunak has granted Sir Keir Starmer permission to start formal access talks with the civil service ahead of a general election this year.
The meetings will be an opportunity for Labour to discuss its agenda for government and establish relationships with potential future colleagues in Whitehall.
Cabinet Secretary Simon Case will oversee and arrange the talks.
Access talks are held in the run-up to a general election, and are the only chance for the Opposition and the civil service to exchange information ahead of a potential handover date after the election.
The Leader of the Opposition must write to the Prime Minister requesting the meetings in order to initiate the process.
By convention, the Prime Minister is expected to respond by authorising the talks ahead of an election.
A Cabinet Office spokesman said: “In line with the long-standing process set out in the cabinet manual, the Prime Minister has authorised access talks between the official opposition and civil service.
“The Cabinet Secretary will oversee and arrange these discussions.”
A Labour source confirmed they had received the letter on Thursday evening and would reply “in due course”.
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