46 Choice of the First Minister.U.K.
(1)If one of the following events occurs, the Parliament shall within the period allowed nominate one of its members for appointment as First Minister.
(2)The events are—
(a)the holding of a poll at a general election,
(b)the First Minister tendering his resignation to Her Majesty,
(c)the office of First Minister becoming vacant (otherwise than in consequence of his so tendering his resignation),
(d)the First Minister ceasing to be a member of the Parliament otherwise than by virtue of a dissolution.
(3)The period allowed is the period of 28 days which begins with the day on which the event in question occurs; but—
(a)if another of those events occurs within the period allowed, that period shall be extended (subject to paragraph (b)) so that it ends with the period of 28 days beginning with the day on which that other event occurred, and
(b)the period shall end if the Parliament passes a resolution under section 3(1)(a) or when Her Majesty appoints a person as First Minister.
(4)The Presiding Officer shall recommend to Her Majesty the appointment of any member of the Parliament who is nominated by the Parliament under this section.