Vermont Sen. Bernie Sanders will lay off "over half" of his campaign staff over the next week, a senior campaign official confirmed to Fox News Wednesday.

Confirmation of the layoffs, which were first reported by The New York Times, came after Sanders vowed to continue his bid for the Democratic nomination despite Hillary Clinton securing a majority of pleged delegates and superdelegates ahead of next month's convention.

The Times reported that most of those being laid off are advance and field staff members, some of whom may be moved to jobs at Sanders' Senate office. Politico reported that campaign personnel whose work isn't related to next month's District of Columbia primary or the convention will be let go. 

"Most of the field staff will likely get their 10-day notice tomorrow because there's no work for then to do," a former Sanders state director told Politico.

Sanders plans to return to his home in Vermont Wendesday before traveling to Washington Thursday for meetings with President Barack Obama and Senate Minority Leader Harry Reid. 

Fox News' Lauren Blanchard contributed to this report.