Mr Javid spoke to MPs about the evolution of the pandemic ahead of the new travel rules which will be introduced tomorrow (December 6).
It follows decisions over the weekend to require pre-departure testing for people traveling to the UK as part of efforts to contain the Omicron variant.
The number of confirmed cases of Omicron in the UK has now reached 336.
England has recorded 64 more confirmed cases of the variant since yesterday, bringing the total number of Omicron cases in England to 261.
Scotland has recorded 23 new cases of the Omicron coronavirus variant in the past 24 hours, bringing the total to 71.
Wales has recorded three more cases, bringing the country’s total to four.
Mr Javid said of the new cases: “This includes cases unrelated to international travel. We can therefore conclude that there is now community transmission in several regions of England. “
“It’s a global battle and we are playing a leading role. “
The term means that authorities trying to trace the source of the infection have found it is spread among UK residents, not just travelers.
Experts have warned that Omicron could become the dominant strain of the virus within a month.
Earlier on Monday, the prime minister defended the new rules that will come into effect on Tuesday against criticism.
Boris Johnson told reporters: “What we are doing is responding to the pandemic.
“We were the first country in the world to take decisive action to fight Omicron. We automatically and immediately put about 10 countries on the red list and we said that anyone coming from any country in the world should be quarantined for a few days.
“We are now going further and toughening these measures as we see Omicron spread around the world. “
The Prime Minister added that the government does not think it needs to change the “general guidance and advice we are giving about Omicron in this country”.
He added: “We’re still waiting to see exactly how dangerous it is, what kind of effect it has in terms of deaths and hospitalizations. “