A group of Brazilian companies has examined the possibility of buying millions of doses of Covid-19 vaccines directly from manufacturers in an attempt to speed up inoculations as the national rollout has faced delays and logistical difficulties.

President Jair Bolsonaro lent his support on Tuesday, saying he was “in favour of this group bringing the vaccine here to immunise 33m people at zero cost to the federal government”.

However, the pharmaceuticals group AstraZeneca has dismissed the idea, saying it was “not possible to make [its vaccine] available to the private market at this time”.

The company has already agreed to provide 100m doses of its jab, developed with the University of Oxford, to the Brazilian federal government as part of a partnership with the Rio de Janeiro-based Fiocruz biomedical institute. An initial batch of 2m arrived earlier this month from India after a delay.

AstraZeneca has warned EU countries, too, to expect significant shortfalls to early deliveries of its coronavirus vaccine due to supply chain issues.

The discussion is likely to raise concerns about queue-cutting for vaccinations. In the less than two weeks since Brazil began inoculating citizens, multiple reports have emerged of politicians and their families receiving preferential treatment.

The talks, which are still in the early stages, centre around a proposal to pool funds to import up to 33m doses of the Oxford/AstraZeneca vaccine, using half to immunise the companies’ employees and family members and the other half donated to the government to distribute to the public, according to a member of the Brazilian Electrical and Electronics Industry Association, which participated in the discussions.

Appetite is being gauged among businesses for participating in such an effort, the trade group said.

The steelmaker Gerdau is one of the companies involved in the discussions. Vale, the world’s largest iron ore miner, said it was invited to participate but declined.

Petrobras declined to comment, although one other individual involved in the discussions said the oil major was “interested in buying 3m doses” through the initiative.

“But then the companies got scared, because I think they thought there could be a problem of reputation, of image, because it could be seen [as] queue-skipping,” the person added.

Brazil’s national vaccination programme was slow to start and has already been hit by supply issues. After much fanfare about the potential for the Chinese-made CoronaVac jab, Latin America’s largest nation was quickly struck by shortages of raw materials, forcing the federal government to lobby Beijing to release crucial pharmaceuticals ingredients.

On Tuesday morning the government of São Paulo — which has spearheaded the roll out of the Chinese vaccine — said materials to make 8.6m more doses would arrive in Brazil early next month.

Some Brazilian state governments have also bet on Russia’s Sputnik vaccine, with Bahia in the north-east of the country agreeing to purchase up to 50m doses.

However, on Monday the country’s health regulator told the Supreme Court it had not received enough material to proceed with the regulatory approval process. Anvisa said that União Química — the Brazilian lab jointly developing the vaccine with Russia’s Gamaleya Research Institute — needed to undertake clinical trials in the country before the vaccine could be granted approval.

Additional reporting by Donato Mancini in London