Sri Lankan President Gotabaya Rajapaksa's resignation will be announced officially at 7:30 a.m. local time (0200 GMT) on Friday, the speaker's office said late on Thursday.
Rajapaksa, who fled the country on Wednesday, submitted his resignation to the parliamentary speaker late on Thursday.
(This story refiles to correct spelling of "resignation" in headline)
(Reporting by Uditha Jayasinghe, writing by Shilpa Jamkhandikar; editing by Jonathan Oatis)