India's omicron Covid count rose to 145 on Sunday after a 45-year-old NRI and a teenage boy, who recently arrived in Gujarat from the United Kingdom, tested positive for the variant.

According to central and state officials, omicron cases have been detected in 11 states and union territories -- Maharashtra (48), Delhi (22), Rajasthan (17) and Karnataka (14), Telangana (20), Gujarat (9), Kerala (11), Andhra Pradesh (1), Chandigarh (1), Tamil Nadu (1) and West Bengal (1).

On Saturday, Maharashtra had reported eight more cases, Telangana's tally jumped from eight to 20, while Karnataka and Kerala reported six and four cases respectively.

In Gujarat, the non-resident Indian tested positive for the coronavirus infection in the RT-PCR test carried out at the Ahmedabad international airport soon after he arrived from the UK on December 15, a health department official said on Sunday.

"The man's sample was later found infected with the Omicron variant," Anand district health officer Dr M T Chhari said.

He was scheduled to reach the state's Anand city from Ahmedabad.

"But, after he tested positive for the coronavirus, he was taken to the Ahmedabad civil hospital from the airport. The patient is currently recovering at the Ahmedabad civil hospital," Dr Chhari said.

His co-passengers and other contacts have tested negative for the viral infection, the official said.

A 15-year-old boy from Gandhinagar was also detected with the Omicron variant after returning from the UK, Gandhinagar Municipal Commissioner Dhaval Patel said.

Maharashtra on Saturday reported eight new infections of the Omicron variant of coronavirus which took the total of such cases in the state to 48, the health department said.

Twenty-eight of these patients have already recovered or have been discharged after testing negative for COVID-19 in subsequent tests, it said.

Of the six cases reported in Karnataka on Saturday, one was a passenger from the UK, while five others were from COVID-19 clusters in two educational institutions in Dakshina Kannada district, officials had said.

In Kerala, the two cases of the new variant of the coronavirus were detected from Thiruvananthapuram in patients aged 17 and 44. One case was detected in Malappuram in a person aged 37 and another was a 49-year-old patient from Thrissur district.

While omicron was first reported in South Africa on November 24, India's first two cases of the this heavily mutated version of the coronavirus were detected in Karnataka on December 2.