India has not banned the export of Covid-19 vaccines, the Union health secretary said on Tuesday, contradicting a claim by the head of the Serum Institute that the government would not allow exports for several months.

The fresh flank was opened on a day a joint statement sought to suggest that a truce has been called overnight after an unseemly and public corporate spat over the vaccines.

“The Union government has not banned the export of any of the Covid-19 vaccines — that is something that should be absolutely clear,” health secretary Rajesh Bhushan said, adding that none of the government agencies that could hypothetically do this had initiated any such move.

The Serum Institute’s chief executive officer, Adar Poonawala, had told the Associated Press on Sunday that India would not allow the export of the AstraZeneca-Oxford vaccine manufactured in India by Serum and exports would not begin until March or April.

Poonawala’s claim had stirred concerns because his company — the world’s largest vaccine maker — is bound to supply half the Covid-19 vaccine doses it produces to poor countries worldwide through Covax, an initiative by international health agencies to ensure equitable access to Covid-19 vaccines.

The Associated Press had quoted Poonawala as saying Serum plans to give 200 million to 300 million doses of the vaccine to Covax by December 2021, balancing distribution of vaccines between India and Covax.

A member of the national Covid-19 task force told The Telegraph it was unclear why Poonawala had claimed there was an export ban.

Health secretary Bhushan, contesting the claim, said: “We should be on guard when such misinformation is sought to be spread.”

Another task force member who is also guiding the vaccination strategy had told this newspaper that there would be no private sales in the early months of the government’s immunisation campaign, but a decision on sales in the private market would need to be taken “at some point”.

Bhushan referred to a statement jointly released by the Serum Institute and Bharat Biotech on Tuesday pledging their vaccines to India and the world.

The Hyderabad-based Bharat Biotech has made an Indian vaccine that, like the AstraZeneca-Oxford vaccine, has received approval from regulators for restricted emergency use in India.

In their joint statement, the two companies which had appeared to question the credentials of the other’s product, said they had a “combined intent to develop, manufacture, and supply the Covid-19 vaccines for India and globally”.

“Both our companies are fully engaged in this activity and consider it our duty to the nation and the world at large to ensure a smooth rollout of the vaccines,” the statement signed by Poonawala and Bharat Biotech head Krishna Ella read.

Poonawala had on Sunday told a television channel that only three vaccines — from Pfizer, Moderna and AstraZeneca — had been proven as effective, the others had thus far been shown as safe as water. His remarks had prompted Ella on Monday to question the quality and quantity of trial data on the AstraZeneca vaccine.

Their comments on the other’s vaccine had stirred worry among sections of scientists who said such remarks threatened to erode the public’s faith in the vaccines.

“Their utterances give an impression to the public that neither vaccine is worth taking — this is really unfortunate,” said Shahid Jameel, a senior virologist and director of the Trivedi School of Biosciences, Ashoka University, Sonipat (Haryana).