As China and some other countries witness a surge in Covid cases, Prime Minister Narendra Modi on Thursday cautioned against complacency, called for strict vigil and directed that the ongoing surveillance measures, especially at international airports, be strengthened.

"Covid is not over yet," Modi reiterated at a high-level Covid review meeting and urged people to wear masks in crowded places, even as the Union Health Ministry asked the Civil Aviation ministry to ensure random post-arrival Covid testing of two per cent of arriving passengers in each international flight at airports from December 24, to minimize the risk of ingress of any new variant of coronavirus in the country.

Amid growing concerns over the spurt in Covid cases in China and some other countries, Health Minister Mansukh Mandaviya said the focus is to ensure that no unknown variant of the virus enters India and at the same time there is no impediment to travelling.

According to a report from Beijing, Chinese health experts have warned that a new wave of coronavirus infections that have hit China may result in new variants.

"We are keeping an eye on the situation (in China). We hope all mankind overcomes the pandemic successfully," External Affairs Ministry Spokesperson Arindam Bagchi said at a media briefing when asked about the surge in Covid cases in China.

Several states also ramped up Covid surveillance and announced a series of measures.

While Karnataka decided to conduct mandatory testing of Influenza Like Illness (ILI) and Severe Acute Respiratory Illness (SARI) and make face masks mandatory in closed spaces and air-conditioned rooms, Tamil Nadu Chief Minister M K Stalin on directed that all passengers arriving at the international airport in Chennai be screened for Covid symptoms.

In Parliament, Lok Sabha Speaker Om Birla advised MPs to wear a mask and spread awareness about Covid-appropriate behaviour. Rajya Sabha Chairman Jagdeep Dhankhar made a similar appeal, saying the House needs to lead the nation by example. Dhankhar and Birla came to the House wearing a mask. Modi also wore a mask in the Rajya Sabha.

Chairing the meeting to assess the Covid situation in the country, Modi urged everyone to follow Covid-appropriate behaviour, including wearing masks in crowded public places, at all times, especially in view of the upcoming festive season, according to a statement issued by the Prime Minister's Office (PMO).

He stressed on the need to ensure that the entire Covid infrastructure at all levels is maintained at a high level of preparedness in terms of equipment, processes and human resources.

Modi advised states to audit Covid-specific facilities to ensure operational readiness of hospital infrastructure, including oxygen cylinders, PSA plants, ventilators and human resources and urged that precaution dose may be encouraged especially for vulnerable and elderly groups.

He also directed officials to ramp up testing and also genomic sequencing efforts.

States have been asked to share a larger number of samples with the designated INSACOG Genome Sequencing Laboratories (lGSLs) for genome sequencing on a daily basis, the PMO statement said.

This will support timely detection of newer variants, if any, circulating in the country and facilitate undertaking requisite public health measures, it added.

The prime minister reiterated that Covid is not over yet and directed officials to strengthen the ongoing surveillance measures, especially at international airports, it said.

Modi was also told by officials that India has been witnessing a steady decline in cases with average daily cases falling to 153 and weekly positivity down to 0.14 per cent in the week ending December 22.

However, 5.9 lakh daily average cases have been reported globally since the last six weeks.

Official sources said the Union Health Ministry is examining the reintroduction of mandatory 'air suvidha' forms with details of RT-PCR test conducted 72 hours prior to travel or complete vaccination proof for passengers coming from China and other countries reporting high number of Covid cases.

In the Rajya Sabha, Mandaviya made a suo motu statement on India's preparedness.

"We are constantly monitoring the situation. There are no direct flights between China and India but people come via other routes," he said.

As a health minister, Mandaviya said he has spoken to many countries and the WHO about what all precautions are needed to be taken and also understand in which direction the pandemic is moving.

Delhi Chief Minister Arvind Kejriwal said the new Omicron sub-variant BF.7 of the coronavirus that is causing a surge in cases in many countries has not been detected in the national capital so far and added his government is fully geared up to tackle any eventuality.

While Kerala and Jharkhand decided to conduct whole genome sequencing of more samples to identify different Covid variants, Gujarat Health Minister Rushikesh Patel said the Covid situation was under control and there was no active case of the BF.7 sub-variant.

Maharashtra Health Minister Tanaji Sawant said international travellers arriving in the state will undergo thermal testing.

Health authorities in Agra also began screening of visitors at the Taj Mahal and other monuments, focusing their efforts mainly on foreign tourists.