Two cases of the Omicron variant of Covid-19 have been discovered in Barnet, the UK Health Security Agency (UKHSA) has said.

The cases were among eight further cases confirmed in England today, bringing the total in England so far to 13.

The exact locations in Barnet have not been disclosed but the individuals who have tested positive and their contacts are isolating.

Work is under way to identify any links to travel to southern Africa, the UKHSA said.

The two cases in Barnet are among nine found so far in London. The others are in Camden (two), Haringey, Westminster (two), Wandsworth, and Sutton.

Scientists are concerned by the Omicron, or B.1.1.529 variant, because it has a high number of spike protein mutations, potentially changing the behaviour of the virus with regards to vaccines, treatments and transmissibility.

All this is still uncertain, and the precautions give scientists time to properly study the new variant.

Dr Jenny Harries, chief executive of UKHSA, said: "We are continuing our efforts to understand the effect of this variant on transmissibility, severe disease, mortality, antibody response and vaccine efficacy.

"Vaccination is critical to help us bolster our defences against this new variant – please get your first, second, third or booster jab without delay."

She added: "Following the change in advice from the Joint Committee on Vaccination and Immunisation yesterday, a booster dose for everyone over 18 years is now recommended at a minimum of three months from your last primary course jab.

"Please take up this offer as soon as you are invited to protect yourself, your families and your communities.

"Please make sure to wear a mask in line with Government guidance, including on public transport and in shops, to help break the chains of transmission and slow the spread of this new variant.

"It is very likely that we will find more cases over the coming days as we are seeing in other countries globally and as we increase case detection through focused contact tracing.

"That’s why it’s critical that anyone with Covid-19 symptoms isolates and gets a PCR test immediately."