Multiple disputes by transport workers could bring London to a halt.
More than 2,000 underground and bus workers are threatening to strike over pay and constrict the vital flow of workers to offices in London.
Strikes that took place last week were "very successful" said Rail Maritime and Transport representative Brendan Judge.
He told the Socialist Worker: "We shut down the operation for four days and we were on a work to rule from Monday to Wednesday this week."
A Transport for London spokesperson said it was disappointed further strikes were being planned as it "would serve no purpose other than to cause unnecessary concern for our passengers".
As the country’s business and financial centre, the City of London is reliant on efficient transport links – it attracts thousands of commuters each day.