Sadiq Khan urged east Londoners to be proud that the biggest investment in the capital’s cultural industry for more than 100 years is being built on their doorsteps.
The mayor of London was at Queen Elizabeth Olympic Park to break ground at the £1.1 billion East Bank culture hub where the BBC, V&A, London College of Fashion and Sadler's Wells are expected to open bases.
Mr Khan said: "East Londoners should be proud that we have broken ground on the biggest investment in our city in culture in more than a century and it is taking place in east London."
When complete East Bank is expected to generate 2,500 jobs and give a £1.5billion boost to the economy.
On whether the jobs would be well paid and skilled, Mr Khan said he didn't want world class facilities which local people don't benefit from.
Ahead of the ceremony, the BBC worked with schools from east London to create a special fanfare to welcome the Mayor.
Afterwards, Newham mayor Rokhsana Fiaz joined her City Hall counterpart on the construction site to bury a time capsule full of things which would provide a snapshot of the capital.
Mr Khan quipped that it was unfortunate there wasn't enough space for the Conservative Party leadership contenders, Jeremy Hunt and Boris Johnson.
The project has received funding including £385 million from London's mayor and £151m from the government.
Westfield Stratford City has also put up £10m for a training and educational programme for residents.
Mr Khan described the development as another jewel in the capital's cultural crown and a project that will transform the fortunes of people living in the area.
Asked his views on the MSG Sphere, a proposed 21,500 capacity entertainment venue which could be built near Stratford station but that some residents were opposed to, Mr Khan said in general it was important to get the balance right.
"We've got to make sure we attract high skilled jobs to our shore, but also make sure we don't inconvenience residents too much. It's about getting the balance right," he said.
University College London, Sadler's Wells and the London College of Fashion are expected to open their East Bank buildings in 2022 with the BBC and V&A following a year later.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here