HAVANA (Reuters) - Cuba said on Wednesday Canada’s decision to withdraw the families of diplomats posted at its embassy due to mysterious illnesses that have affected both its staff and that of the U.S. embassy in Havana was “lacking justification.”

Canada and the United States say some of their diplomats posted on the Communist-run island have reported symptoms such as dizziness, headaches and nausea since late 2016, with medical specialists even detecting possible brain injuries.

Canadian and U.S. investigations have so far not turned up a cause for the illnesses but both countries have said it could be man-made.

Canada said on Monday it was making Cuba an “unaccompanied post” for its diplomats due to the “ongoing uncertainty”.

The United States last year did the same but went much further, reducing staffing levels to their lowest since the 1970s and issuing a warning on travel to Cuba.

“The Cuban government respects the Canadian government’s decision but considers it lacking justification,” Cuba’s foreign ministry said in a statement. “It ratifies with all responsibility that Cuba is a safe country.”

Havana said its investigation had found no evidence for the illnesses reported by the Canadian diplomats and no indication of any kind of attack or incident.

“Our country will continue working constructively with the government of Canada ... in order to find conclusive explanations for the reported ailments.”

Canada said there had been no new incidents since the fall of 2017 but diplomatic families that had returned to Canada had continued to experience symptoms.