Cracks are visible on some of the chimneys and need to be rebuilt for safety reasons and to ensure they last, say the developers.
But campaigners say taking the chimneys down will ruin the character of the building.
A small group of people dressed as monkeys gathered outside the station today with placards claiming the company behind the development 'don't give two monkeys' for the iconic building.
More top news
Hundreds of people do no know when they will be allowed back home after a 'serious incident' was declared in east London.
A Tube and rail strike planned for Wednesday evening could bring the capital to a standstill causing travel chaos for millions of commuters
The only Muslim survivor of the 7/7 terror attack in London has urged the country to stand together against Islamophobia.