LONDON (Reuters) - Any move by the European Union to limit vaccine exports to Britain would be a worry and jeopardise the target of vaccinating the most vulnerable by mid-February, an English health chief said on Tuesday. “Were that to happen, then of course that would be a worry,” Simon Stevens the chief executive of NHS (National Health Service) England told lawmakers, adding that he shared the view of the government’s vaccine minister that he did not think problems were likely. “I think (doctors) and hospitals and all of our partners are doing well to get the vaccinations now underway quickly. So we don’t want any of that progress stymied.”