While Khan was jailed this month, Pakistan’s parliament was dissolved at the request of his successor Shehbaz Sharif to pave the way for a caretaker government that will hold elections in the coming months.
No date for the election has been announced yet.
Khan, a former cricket star, swept to power in 2018 on a wave of popular support, an anti-corruption manifesto and support from the powerful military establishment.
When he was ousted in April last year, analysts said it was because he had lost the support of the same generals who handed him the keys to office.
They were replaced by a shaky coalition of dynastic parties that have historically ruled Pakistan.
But as an opposition politician, he launched an unprecedented campaign against influential generals who staged at least three successful coups in decades of martial law.