It is understood that his job has been made redundant. It is not known if he has a job to go to.
Williamson joined Samsung Mobile in the middle of last year. He was charged with overseeing marketing and product management and reported directly to Mark Mitchinson, vice president for Samsung Mobile for the UK and Ireland.
Prior to that role Williamson worked at T-Mobile as director of core business.
In other recent senior departures, Samsung UK general manager for sales, Jon French, announced his intention to leave the company and join HTC as UK and Ireland country manager.
His replacement is yet to be announced.
At the end of last year Samsung Electronics UK appointed former Sony general marketing manager, Mikah Martin-Cruz, as its new head of marketing.
In marketing news, Samsung Electronics this month launched a £5m marketing campaign to support the launch of its latest smartphone, Jet.