Speaking at an event discussing the latest findings of the British Social Attitudes survey and hosted by the National Centre for Social Research, Curtice said that Reform had grown by appealing to socially conservative voters, but were much more split on economics, with the economic right only having a six-point lead over the economic left among the party’s support.

Social liberals were defined as those comfortable living in a diverse society, while social conservatives as people who want coherence around common national moral codes and identities.

Curtice said that Reform’s support was more rooted in socially conservative spheres that went beyond traditional indicators of people’s political persuasion.

“The terms ‘right’ versus ‘left’ do not capture the distinctiveness of Reform,” Curtice said. “Rather, Reform support is socially conservative Britain, of which supporting Brexit is a very much a signifier.

“Crucially, what you need to understand is that whether you are right wing or left wing is almost wholly unrelated to whether you are a social liberal or a social conservative. These are two dimensions, and our political space is now two dimensional rather than one dimensional.”

Reform’s recent success was likely due to the departure of Brexit supporters from the Conservatives, Curtice added, saying that while turning around the NHS and the economy might help parties restrict Reform’s growth, it is unlikely to do so alone.

This has implications for parties’ election strategies, he said. “The traditional politics of the Conservative and Labour parties is that you create relatively large coalitions of voters, and doing that, in the case of the Conservatives, [by being] a wee bit to the right of centre, and, in the case of Labour, a wee bit to the left of centre,” Curtice explained.

“The problem now, however, is the… proportion of people who are in the centre on both dimensions is inevitably much smaller than the proportion of people who were in the centre when our politics were uni-dimensional.”

Therefore, parties would find it more difficult to win elections from the traditional centre ground in a two-dimensional political landscape where social and economic beliefs are no longer operating in tandem.

“Structurally, the game is different,” said Curtice, and “trying to occupy the centre ground is no longer necessarily an effective strategy.”

For Labour, Curtice added: “The Labour party’s principle problem is not Reform; its principle problem in terms of voters are the Greens, and the fact the Greens are picking up the more socially liberal and left-wing end of the Labour coalition.”

With Reform polling on average between 27% and 28% of the electorate, Curtice said that this vote share had never been a winning number in an election before, but that the fragmentation of the UK’s politics could make it so. “There is clearly, likely, to be a plateau to what [Reform] can achieve,” he said.