Ensuring Local people are employed for large events in our city

There have been a couple of large scale events in the city this summer where opportunities to be involved have been restricted to companies and vendors from outside the city. I.e. Glorious Day on Hove Lawns in June. Is it / can in be a condition of commissioning / contracting to create / offer a minimum number of opportunities to local people - whether that's as hospitality staff, production crews, security, food suppliers etc.