India’s active COVID-19 caseload, however, has fallen to 2.14 lakh, the lowest after 197 days.
The sample of the UK returnee was sent to NIV Pune from the VRDL, JNIMS in Imphal on January 4.
As flight operations between India and the United Kingdom resumed, more than 250 passengers from the UK have arrived in Delhi in the first flight on Friday.
On Tuesday, British Prime Minister Boris Johnson, who was to be the chief guest at the Republic Day parade in New Delhi, cancelled his visit to India over the coronavirus crisis in the UK.
The 20 new cases have been identified at NIV, Pune.
Comprehensive contact tracing has been initiated for co-travellers, family contacts and others.
Oxford-AstraZeneca is the second coronavirus vaccine to be authorised for use in the UK after the Pfizer-BioNTech vaccine
The six patients, who had recently returned to India from the United Kingdom, have been kept in single room isolation in designated healthcare facilities by the respective state governments.