After further discussions between Shepherdson and Green today, Topshop issued a statement this afternoon confirming that the two had agreed a parting of the ways, because Shepherdson decided it was 'time for a change'.
Reports this morning suggested that Shepherdson - who has been widely credited with reviving the fortunes of the fashion retailer - had fallen out with Sir Philip over the appointment of model Kate Moss to design a collection.
However, the company sought to dispel the rumour that Shepherdson's departure was because of Moss's appointment.
It said: 'Sir Philip and Jane would like to confirm their unanimous agreement to sign a design collaboration with Kate Moss for Topshop, and this has absolutely nothing to do with her decision to leave the business.
'Sir Philip and Jane have been in discussions over the past few weeks and, as a result, Jane has decided that after a long commitment to Topshop it is time for a change.'
Shepherdson's role will be divided between buying director Karen Fenn and commercial and merchandising director Mary Homer.