Prime Minister Boris Johnson's address to the nation was watched live by an estimated 26.5 million viewers last night, according to early ratings data.
The statement, which saw Johnson confirm a UK-wide lockdown due to the coronavirus, broke into regular schedules at 8.30pm.
BBC One's version of the broadcast attracted 15.4 million, while 5.5 million watched the simulcast on ITV and 1.5 million watched on Channel 4.
A further 4 million people tuned in on Sky News, BBC News channel and other stations to amount to a combined audience of at least 26.5 million.
The figures make Johnson's address the most-watched event broadcast in the UK since 1973, when 27.6 million watched Princess Anne get married for the first time.