Shadow health secretary Wes Streeting urged voters not to give “matches back to the arsonist to finish the job”, as he suggested a Conservative election victory would be a “nightmare on Downing Street”. The Labour frontbencher warned against “breathtaking complacency” over opinion polls predicting a victory for Keir Starmer’s party at the general election. The transport secretary, Mark Harper, said Labour will have a “blank cheque” if they win the 4 July general election with a large majority. Wes Streeting failed to rule out an overhaul of the council tax system if Labour win next month’s election and said his party wanted to do more in power than it had promised in its manifesto. The shadow health secretary told BBC One’s Sunday with Laura Kuenssberg none of his party’s manifesto pledges required a rise in council tax. But pushed by the presenter to rule out the country’s first revaluation since 1991, he refused to do so. Polling expert Prof John Curtice said support for the Conservative party is now at its lowest ever in British polling history. “Every poll has reported a fall in Conservative support and nearly all the narrowing of the Conservative lead over Reform,” he told the BBC. “So, what last week was an average eight point Conservative lead over Reform has now halved to just four points – and standing at just 20%, Conservative support is now at its lowest ever in British polling history.” His comments came after the latest Opinium poll for the Observer showed a shift away from the main parties. Plaid Cymru leader Rhun ap Iorwerth accepted that the 4 July poll “isn’t an independence election”, while in Scotland, SNP leader John Swinney accused the Tories and Labour of threatening the NHS. Analysis by the Nuffield Trust thinktank suggested both Labour and Tory pledges on the NHS would leave the health service with lower annual funding increases – at 1.1% and 0.9% respectively – than during the austerity era. Thank you for reading and all your comments today. This blog is closing now but you can read all of our politics coverage here.