Labour manifesto was strongest since 1945, Corbyn constituency chair says

In an email, Alison McGarry thanked members for their hard work in the North London constituency and in marginal seats "far and near" for the 12 December election.

She said: "I have worked on elections since 1970 and this was the most positive, supportive, enthusiastic campaign I have ever worked on.

"The Labour Party had its strongest manifesto since 1945, a manifesto that rejected Johnson's hard Brexit narrative, fundamentally opposed neoliberalism and offered transformative policies for a green industrial revolution."

Labour has started a postmortem into its heaviest election defeat since the 1930s. The party lost 59 seats as it shed support to the Conservatives in towns in its traditional Northern heartlands while remaining strong in London and other cities. McGarry's message appears to reflect that divide.

Polls have shown Corbyn's leadership and the scale of Labour's policy ambitions were factors in Labour's defeat on top of Brexit. The party published a weighty manifesto promising nationalisation of major industries, free broadband, higher minimum pay and a surge in public investment.

Len McCluskey, general secretary of the Unite union, has criticised the party's "incontinent rush of policies" and its indulging of metropolitan members over longstanding working class voters.

“The next leader needs to understand the communities that gave birth to the labour movement, and realise that the whole country is not very like Labour London," McCluskey told the Huffington Post.

"Too often, Labour addresses the metropolitan wing of its electoral coalition in terms of values – openness, tolerance, human rights – and the ‘traditional’ working-class wing simply in terms of a material offer, as if their constituencies did not have their own values of solidarity and community."

Corbyn's election prompted a surge in Labour's membership as leftwing activists joined the party. As Corbyn's potential successors begin setting out their positions, his critics have expressed concern that the party's members will stick with his formula instead of facing electoral reality.

McGarry, a member of the Corbyn-supporting Momentum movement, has said she became more active in the party after Corbyn became leader. Corbyn has represented Islington North, a tightly packed, urban constituency with high poverty levels, since 1983 and was re-elected with a reduced majority of 34,603 on 12 December.

In her email, McGarry said: "We are all hugely disappointed by the defeat and its impact on our families and communities. We are now pausing to look objectively at our organising and campaigning strategies but will return undaunted to our campaigning for social justice in the new year."

Sharecast emailed McGarry and Islington North Labour party for comment.