The first unsuccessful candidate will be knocked out next Wednesday.
The Tory leadership hopeful may be regretting his "credible, persuasive" economic plan after this.
"It is not something that you can solve by leaping onto some magical ideological square," the shadow pensions secretary said.
The Tory leadership contender said the Reform UK leader's response to the tragedy was "not helpful".
The winner will be the sixth Conservative Party leader since 2016.
The winner will be the sixth Conservative Party leader since 2016.