Elections in Ukraine are held to choose the president (head of state), Verkhovna Rada (legislature), and local governments. Referendums may be held on special occasions. Ukraine has a multi-party system, with numerous parties in which often not a single party has a chance of gaining power alone, and parties must work with each other to form coalition governments. Imperative mandate (Ukraine) Elections in Ukraine are held to choose the President (head of state) and Verkhovna Rada (legislature). The Ukrainian constitution does not allow to hold elections while martial law is in effect. The president is elected for a five-year term. The Verkhovna Rada has 450 members and is also elected for a five-year term, but may be dissolved earlier by the president in the case of a failure to form a government. The next election to the Verkhovna Rada, set to be in 2023, will be, for the first time, with different regional open lists (with again an electoral threshold of five percent) and a return, and thus abolition of the constituencies with first-past-the-post voting, to only one national constituency. From 2012 until the 2019 Ukrainian parliamentary election the Verkhovna Rada was elected using a mixed election system. Half of the representatives were elected from national closed party lists distributed between the parties using the Hare quota with a 5% threshold. The remaining half were elected from constituencies using first-past-the-post voting. This system was adopted for the 2012 elections and was also used for the 2014 election, as a new draft law moving to electing all members using open party lists failed to gather necessary support in the Rada. According to current law, the next election to the Verkhovna Rada (to be held) in 2023 will again be without single-member constituencies and instead deputies can only be elected on a party list in one nationwide constituency with a 5% election threshold with open regional lists of candidates for deputies. A snap poll must have a voter turnout higher than 50%.