Labour deputy leader Angela Rayner will take on the party’s levelling up brief as Sir Keir Starmer reshuffles his top team to claim he has a government in waiting.

The reshuffle was put into gear after shadow environment secretary Jim McMahon announced he is standing down to focus on his health.

Ms Rayner, in a widely predicted move, has been shifted to focus on a brief that includes local government, housing and the so-called levelling-up agenda, which involves scrutinising the Conservative Government’s pledge to create economic opportunities outside London and the South East.

As part of the revamp, Ms Rayner has formally been appointed shadow deputy prime minister, having faced Oliver Dowden at the despatch box during Deputy Prime Minister’s Questions when Rishi Sunak is away.

She had previously been shadowing the Cabinet Office.

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Lisa Nandy, one of Sir Keir’s leadership rivals in 2020, was previously shadowing Levelling Up Secretary Michael Gove, but has seen his role on the frontbench downgraded.

The former shadow foreign secretary was demoted to shadow cabinet minister for international development during the reshuffle – a position that does not directly relate to the work of a secretary of state in Government.

Ian Murray, Labour’s only MP representing Scotland, remains the shadow Scottish secretary.

Sir Keir’s decision to create a new-look team comes as he uses Parliament’s return from the summer recess to further set out his vision for government.

In an interview with the Daily Mirror, the Opposition leader promised not to raise income tax if he wins the next general election, which is likely to be held next year.

Sir Keir has backed away from tax rises since pledging to increase income tax for the top 5% of earners during his leadership bid three years ago, instead emphasising his aim to secure the highest economic growth in the G7.

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Mr McMahon, who had been expected to lose his position, told Sir Keir in a letter on Monday that he has faced “a number of personal challenges in the last year, coming back from a serious illness”.

Publishing his resignation letter on X, formerly known as Twitter, the Oldham West and Royton MP said he remains a “firm supporter of Keir” despite his decision to resign.

He added: “After a testing year I want to focus on getting my health back to full strength so that I can make a full and active contribution to the general election campaign heading towards us, and to prioritise my constituents.”

Sir Keir, in a letter also published on X, thanked Mr McMahon for his work in the shadow cabinet, which included a stint in charge of the transport brief.

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He said he is aware Mr McMahon has faced a “number of personal challenges in addition to your frontbench work and that these have taken a personal toll”.

The Opposition leader signed off his letter saying he looks forward to “working with you again in the future”.

Moments after the exchange, Labour announced Ms Rayner’s shadow cabinet switch.

A Labour source said: “Keir is delighted that Angela has accepted this important role; in addition she will continue to be the strategic lead on Labour’s new deal for working people.”

The pre-election shake-up comes on the same day that former top civil servant and partygate investigator Sue Gray starts her new role as the Labour leader’s chief of staff, according to the BBC.

The anti-sleaze watchdog, the Advisory Committee on Business Appointments, had recommended a six-month delay to her starting the job with Sir Keir – advice Labour accepted.