The Zinoviev letter, which Zinoviev himself denied writing, is published in the Daily Mail; the Labour party would later blame this letter for the Conservatives' landslide election win four days later.

The Zinoviev letter was a forged document published and sensationalised by the Daily Mail newspaper four days before the 1924 United Kingdom general election, which was held on 29 October. The letter purported to be a directive from Grigory Zinoviev, the head of the Communist International (Comintern) in Moscow, to the Communist Party of Great Britain (CPGB), ordering it to engage in seditious activities. It stated that the normalisation of British–Soviet relations under a Labour Party government would radicalise the British working class and put the CPGB in a favourable position to pursue a Bolshevik-style revolution. It further suggested that these effects would extend throughout the British Empire. The right-wing press depicted the letter as a grave foreign subversion of British politics and blamed the incumbent Labour government under Ramsay MacDonald for promoting the policy of political reconciliation and open trade with the Soviet Union on which the scheme appeared to depend. The election resulted in the fall of the first Labour government and a strong victory for the Conservative Party and the continued collapse of the Liberal Party. Labour supporters often blamed the letter, at least in part, for their party's defeat.