(CNN) -- The Biden administration is developing a plan to mandate vaccinations for almost all foreign visitors to the US, a White House official confirmed to CNN on Wednesday, though some exceptions are expected. Officials are still in the early phases of developing the plan and an announcement is not imminent. There is no imminent change to the current travel restrictions in place because of the highly contagious Delta variant currently circulating around the world, an official cautioned. But officials from multiple agencies across the federal government have been constantly evaluating the current travel restrictions and are developing a plan for lifting them when the time eventually comes. According to the White House official, this includes requiring all foreign nationals traveling to the US from all countries to be fully vaccinated, with limited exceptions, though a final plan has not been determined.