Michael Gove warned the UK faced a “deeply concerning situation” given the fast rate of the Omicron spread.
It comes as the UK will battle one million Omicron cases by the end of December, experts have warned.
However, the Health Security Agency also found boosters provide 70-75% protection against the variant.
London has seen a sharp rise in Covid cases as the UK recorded its highest daily infection rate since January.
It comes as the UK reported 58,194 new coronavirus cases today - the highest daily total since January. A further 120 deaths have also been recorded.
The warning came as face masks became mandatory in more settings including cinemas, theatres and churches while the Government rolls out its new “Plan B” restrictions.
The tougher measures - which from Monday will also include vaccine passports and working from home - are designed to slow the spread of the new Omicron variant of Covid-19, which is surging in several parts of the country including London.
