McDonnell, who has been the MP for Hayes and Harlington since 1997, is widely regarded as Corbyn’s closest political ally and as representing the Left wing of the party. He has previously advocated nationalisation without compensation, as well as bringing banks under state control and indicated he favours a 60p tax rate and the introduction of a financial transaction tax.  He is currently chair of the Socialist Campaign Group and the Public Services Not Private Profit Group.

Some Labour MPs have voiced disappointment that the role of shadow Chancellor, which was previously filled by Ed Balls until he lost his seat in the May election, was not given to Angela Eagle. They argued that this would have increased the number of women and more centre-leaning MPs in Corbyn’s shadow cabinet. 

Seema Malhotra is named as shadow chief secretary to the Treasury. A former Accenture and PwC management consultant, she has been the MP for Feltham and Heston since 2011.

As part of his support for Corbyn’s campaign, McDonnell outlined future Labour policies to tackle the deficit which he said would be done by ‘halting the tax cuts to the very rich and to corporations, by making sure they pay their taxes’, as well as by additional investment in housing and infrastructure.

In a letter to Labour supporters ahead of the leadership vote, McDonnell wrote: ‘Our cuts will be to the subsidies paid to landlords milking the housing benefit system, to the £93bn in subsidies to corporations, and to employers exploiting workers with low wages and leaving the rest of us to pick up the tab’.

McDonnell said he supported a Corbyn leadership which would introduce ‘an effective regulatory regime for our banks and financial sector; a full-blown Glass-Steagall system to separate day-to-day and investment banking; legislation to replace short-term shareholder value with long-term sustainable economic and social responsibilities as the prime objective of companies; radical reform of the failed auditing regime; the extension of a wider range of forms of company and enterprise ownership and control including public, co-operative and stakeholder ownership; and the introduction of a financial transactions tax to fund the rebalancing of our economy towards production and manufacturing.’

Public ownership is a key plank of the strategy McDonnell outlines, but he says this would be achieved ‘through smart forms of 21st-century common ownership and control’.

One example would be renationalising the railways with a form of joint management involving workers and passenger representatives, while the energy market would be expanded from the current big six energy companies to include renewable energy production and supply by local communities, local authorities and co-ops.

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