The Westcountry could have been home to a national vaccine centre, but the Government rejected the idea.
A boss from one of the firms involved in the Gravity site, at Huntspill near Bridgwater, says he approached the Government six weeks ago.
Ministers chose to build a facility near Oxford to eventually produce Covid-19 vaccines instead.
The 635-acre Somerset site - which will connect to a new link road at M5 Junction 23 - is still being built and aims to become a hub for things like research and development, artificial intelligence, robotics and electric vehicles.
Martin Bellamy, the chairman of Salamanca Group, argued the Gravity site was 'shovel ready' and would allow the UK to increase capacity and lead global production.
The Department for Business said: “We have invested £131 million for the Vaccines Manufacturing and Innovation Centre to produce enough doses for the entire UK population in six months when it opens in summer 2021.”