New Chancellor of the Exchequer Nadhim Zahawi (left) and new Health Secretary Steve Barclay. (Photo: Reuters)

Steve Barclay, previously chief of staff at Downing Street, has been appointed Health Secretary, and Nadhim Zahawi, previously Secretary of State for Education, replaces Sunak as the new Chancellor of the Exchequer.

In their resignations, posted online earlier in the day, Javid and Sunak made clear their disapproval of Johnson's leadership. Javid said he "can no longer, in good conscience, continue serving in this government", while Sunak criticized the government's lack of competence.