Lausanne-based Mitchell Communications Agency (MCA) are to replace JTA as public relations consultants for the European Olympic Committees (EOC), insidethegames understands.
The company, run by former International Olympic Committee (IOC) media relations employee, Andrew Mitchell, is expected to be officially unveiled in the position at next month's EOC Executive Committee meeting and Seminar in Belgrade.
British-based JTA had assisted the EOC's communications drive over the 2015 European Games in Baku, as well as during their re-branding and logo launch in 2016.
Mitchell helped communications surrounding the Vancouver 2010, London 2012, Sochi 2014 and Rio 2016 Olympic Games before leaving two years ago.
The IOC remain one of his clients along with SportAccord, where he was involved in the World Sport and Business Summit which took place in Bangkok last week.
His website also lists European Athletics, the World DanceSport Federation and the Pully Lausanne Foxes basketball team as clients.
Preparations for the second European Games in Minsk next year are expected to be the main area where MCA will be required to assist the EOC in the short-term.
Criticism of Belarus' censorship and poor human rights standards are bound to dominate coverage of the event, as they did before Baku 2015.
Belorussian-Ukrainian freelance opposition journalist Dzmitry Halko was detained last week and faces up to six years in jail on suspicion of assaulting a police officer in what is being considered as the latest example of a crackdown by the regime of Alexander Lukashenko.
JTA chairman Jon Tibbs admitted that they had hoped to continue working with the EOC, but hailed other newly acquired clients including the International Testing Agency set-up to administer the global drug testing system.
They also still work for organisations including the Association of National Olympic Committees and International University Sports Federation.
"Whilst this [the EOC decision] is a disappointment, it has not come as a complete surprise," Tibbs told insidethegames.
"The EOC face some tough challenges ahead in dealing with the next edition of the European Games and securing appropriate host cities and commercial partners for future editions.
"They decided to turn to a new communications partner to help them face these challenges and we wish the EOC and their new agency every success in the months and years ahead.
"Meanwhile, JTA business goes from strength to strength and we have recently won two important new pieces of business, the International Testing Agency and the International Tennis Federation.
"In addition, we will be announcing further new business wins in the next few weeks.
"Our plans to open an office in Switzerland and Beijing in the near future, remain firmly on track."