May has accused European Union officials of seeking to sway the outcome of the election by issuing threats over Brexit, and warned voters that the other 27 member states were lining up against Britain to win a deal that "works for them".
The figure is based on a study of all the parties' performance by Sky's election analyst, Professor Michael Thrasher.
The party looked set on Friday night emerge with fewer council seats than before the election.
Meanwhile, Labour slumped to become the third largest party in Scotland's councils, and was kicked out of power in its Glasgow heartland for the first time in nearly 40 years.
Meanwhile, Tory candidate Ben Houchen scored a significant win in the Tees Valley mayoral race by more than 2,000 votes, after a run-off against Labour's Sue Jeffrey.
Among her opponents licking their wounds was, as expected, Jeremy Corbyn with almost 400 losses that even included Glasgow city council.
But Jeremy Corbyn's party did win mayoral contests in Liverpool and in Greater Manchester - where former health secretary Andy Burnham was elected with more than 60% of the votes.
The Tories gained 500 seats and seized control of 11 councils.
Labour supporters will see the controversy around the interview as more evidence of a media biased against Labour and looking to debate style rather than a shortage of police officers, while Liberal Democrat supporters will see a party leader at ease debating critics.
British Prime Minister Theresa May's Conservative Party has opened up the biggest lead on record for polls conducted by research firm ICM, suggesting it remains on course for a sweeping win in a national election in a month's time.
The largest party in terms of seats by a considerable margin, the SNP secured nearly a third of all first preferences cast in the local polls while the Tories won just over a quarter.
"I will not take anything for granted", May insisted.
Mr Corbyn, whose leadership had been widely criticised from within the Labour ranks, described the results as "mixed" and claimed the party was "closing the gap" on the Conservatives.
Conservatives have made historic advances in local elections across the United Kingdom, gaining more than 500 councillors, winning tightly-fought battles for elected mayors in the West Midlands and Tees Valley and forcing Labour into third place in its former stronghold of Scotland.
Ms Sturgeon said: "What we've seen across Scotland today of course is the SNP vote holding firm".
It meant a substantial gain for the Tories - who now have 56 councillors.
In West Sussex the Conservatives increased their grip, swamping both the Lib Dems and Labour. Labour performed better in Wales, retaining control in Cardiff and other cities and losing seats to Independents rather than the Conservatives.