Labour has kicked off selections for a series of key target seats as officials aim to complete Jeremy Corbyn’s transition from political outsider to socialist prime minister.

The party has imposed application deadlines of October and early November for 15 of the constituencies which it believes it can take as it seeks the 64 extra MPs needed to form a Commons majority.

The first round of selections includes bellwether seats Thurrock, in Essex, and Northampton North, as well as others which now appear appear marginal following Labour’s surprise performance at the general election, such as Shipley in West Yorkshire and Camborne, Redruth and Hayle.

The list, published on Labour’s website, confirms many of the seats which featured on the leaked list of 75 target seats which was passed to LabourList last month.

It also provides an update on which constituencies have been earmarked for all-women shortlists, including Arfon, Erewash, Rugby and Shipley.

Labour needs to achieve a national swing of 3.6 per cent if it is to gain the 64 seats required to reach 326 MPs and achieve a majority of one in the Commons.

The target seats where Labour is selecting candidates this autumn.