A total of 20 people who returned to India from the United Kingdom have tested positive for the new coronavirus variant so far, the Union ministry of health and family welfare announced on Wednesday.

On December 29, the government said six UK returnees have been found to be positive with the new UK variant genome. The samples of all passengers who tested positive after flying from the UK are being sent to laboratories for genome sequencing.

All the infected people are now in isolation, the health ministry said in a statement, adding that their fellow travellers and close contacts are being traced and quarantined. Genome sequencing on other samples is currently going on.

Ten laboratories across the country will be carrying out genome sequencing. The list includes NIBMG Kolkata, ILS Bhubaneswar, NIV Pune, CCS Pune, CCMB Hyderabad, CDFD Hyderabad, InSTEM Bengaluru, NIMHANS Bengaluru, IGIB Delhi and NCDC Delhi.

The new strain - believed to be significantly more transmissible - has been spreading fast across the world amid global fears and fresh travel restrictions after the UK said earlier this month the virus was "out of control".

Many countries, such as Denmark, the US, Netherlands, Australia, Italy, Sweden, France, Germany, Canada, and Japan have reported cases of the new coronavirus variant.