Reform have topped a Sky News/YouGov poll for the first time as the party continues to shake up British politics.
Nigel Farage's Reform UK has edged in front on 25%, with Labour pushed into second on 24% and the Tories on 21%.
The YouGov poll, taken on Sunday and Monday, also puts the Lib Dems on 14% and Greens on 9%.
All the polling moves that push Reform UK to the top for the first time this week are within the margin of error and the overall picture remains unchanged - with Britain in a new period of three party politics in the polls.
However, the symbolism of Reform UK topping the poll is likely to be seized on by MPs from all parties.
One in five Tory voters at the last election would now vote for Reform.
The Tories are likely to be the hardest hit by the poll, having been in third place since YouGov restarted polling after the general election.
The Sky News/YouGov poll also found Kemi Badenoch has slipped behind Nigel Farage when voters are asked whether they have a favourable or unfavourable opinion of the leaders.
Last month, Badenoch has a net favourability rating of -25, but that has now dropped to -29 this month.
This puts her below Farage, who had a net favourability rating of -32 last month, which has now risen to -27 this month.
Keir Starmer is less popular than both Farage and Badenoch, with his net favourability rating now at -36.
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