Singh had earlier said he felt betrayed by both Rajnath Singh and Vasundhara Raje, even though he had supported the two for the posts of BJP president and Rajasthan chief minister respectively.
This was the second time in five years that Jaswant Singh was expelled from BJP.
In 2009, he had been expelled for his controversial book praising Pakistan founder Mohammed Ali Jinnah. However, he was taken back in the party-fold in June 2010.