Jeremy Corbyn will address protesters at an anti-austerity demonstration in London later.
The Labour leader will be joined by the party's shadow chancellor John McDonnell, as well as other speakers at Parliament Square on Saturday.
Protesters will gather outside BBC Broadcasting House in Portland Place at about midday where speakers will include Owen Jones and MP Diane Abbott.
From there they will march to Parliament Square where union leaders Len McCluskey and Frances O'Grady will join Mr Corbyn and others.
The event has been organised by the People's Assembly Against Austerity.