Is the UK a two party system?

Firstly, what is the question asking?Essentially, this question is asking whether or not UK politics is dominated by just two parties (Conservative and Labour) or if instead minor parties have more of an influence on UK politics than we think?Yes the UK has a two party system: First Past the Post voting system and its majoritarian nature favours larger parties' success2017 and 2019 election results show support for two main parties remains high...No the UK has a multi party system:The increase in use of referendums is arguably due to pressure from minor parties, e.g. 2014 (ScotIndy) 2011 (AV) 2016 (EUref)Places with a more proportional system of voting show symptoms of being a multi party system, e.g. Welsh Assembly, EU Parliament.High post-war levels of support for Tory+Lab due to inherent class cleavages, now arguably, issues that transcend party lines define how you vote; European question, climate and so on.Conclusion:It depends hugely on the system of voting used, therefore, in Westminster it could be said a two party system is present, however, you only have to look elsewhere to see evidence of minor parties leveraging huge power, e.g. referendums.