(1) The office of President shall become vacant if the holder of the office--
(b) resigns, in writing, addressed to the Speaker of the National Assembly; or
(c) otherwise ceases to hold office under Article 144 or 145 or under any other provision of this Constitution.
(2) When a vacancy occurs in the office of President --
(a) the Deputy President shall assume office as President for the remainder of the term of the President; or
(b) if the office of Deputy President is vacant, or the Deputy President is unable to assume the office of President, the Speaker of the National Assembly shall act as President and an election to the office of President
shall be held within sixty days after the vacancy arose in the office of President.
(3) A person who assumes the office of President under clause (2) (a), or following an election required by clause (2) (b), shall, unless otherwise removed from office under this Constitution, hold office until a newly elected President is sworn in following the next regularly scheduled election under Article 136(2)(a).
(4) If the Deputy President assumes office as President under clause (2) (a), or a person is elected to the office of President under clause (2) (b), the Deputy President, or the person elected, shall be deemed for the purposes of Article 142 (2)--
(a) to have served a full term as President if, at the date on which the person assumed office, more than two and a half years remain before the date of the next regularly scheduled election under Article 136 (2)(a); or
(b) not to have served a term of office as President, in any other case.