Prime minister leader, the incoming leader will usually be referred as "prime minister-in-waiting". An example or this situation was in 2016 in the United Kingdom when Theresa May was elected leader of the Conservative Party while David Cameron was still prime minister. Ukraine's constitution (1996) lists the powers, functions and duties of the Prime Minister of Ukraine. Most prime ministers in parliamentary systems are not appointed for a specific term in office and in effect may remain in power through a number of elections and parliaments. For example, Margaret Thatcher was only ever appointed prime minister on "one" occasion, in 1979. She
First Vice Prime Minister of Ukraine to Prime Minister, all office duties of the First Vice Prime Minister are supported by the Secretariat of Cabinet of Ministers. Along with other members of Cabinet of Ministers, the newly appointed First Vice Prime Minister takes one and the same oath of office at a plenary session of the Verkhovna Rada (Ukrainian parliament). According to the Article 10 (Law of Ukraine about the Cabinet of Ministers), a member of Cabinet of Ministers (except for the Prime Minister of Ukraine) who refuses to take the oath is considered as such who refused to accept the post. Every newly appointed member