It comes as Boris Johnson last week approved the demolition of Earls Court, which would see the 32-hectacre site transformed into more than 6,700 homes, alongside infrastructure and public realm improvements, over a 20-year construction period.
Halwagi said: "The Mayor’s decision is a huge disappointment and a clear message that he isn’t listening the very people he claims to serve.
"The decision also highlights a blinkered and biased perspective, without proper and educated consideration of the longer term, detrimental effects this will have for the UK exhibitions and events industry and the UK economy as a whole."
He added that with a purported vision for London to be a leader among world cities – as stated on the GLA website – this move has "condemned the capital to fall even further away from leading world cities".
"We are 36th in the world on venue space and Paris successfully sustains two major venues in the world’s top ten," Halwagi said. "We will not let this decision rest."
The EC Properties project, designed by architects Terry Farrell and Partners, was passed to the Mayor for his consideration after being given the go-ahead by both Kensington & Chelsea Council and Hammersmith & Fulham Council last year.
Johnson said: "I’m in no doubt that the development proposed for Earls Court and West Kensington will provide a massive boost not just to this part of the capital, but to London’s wider economy as well.
"It is a landmark project that will deliver much needed jobs, new homes and improved infrastructure and will make this strategically important part of the capital an even better to place to live, work and visit."
What are your thoughts on the Mayor's decision to approve the Earls Court redevelopment plans?
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