A letter has revealed how former prime minister Kevin Rudd held an intervention meeting with Pfizer to try to bring forward millions of COVID doses as Australia’s rollout lagged.

Mr Rudd spoke to Pfizer chairman and chief executive Albert Bourla on June 30 to ask if the drug company could “advance the dispatch of significant quantities of the Pfizer vaccine to Australia as early as possible in the third quarter of this year”.

Days later, Prime Minister Scott Morrison announced Pfizer doses would rise to 1 million doses a week after states complained bitterly about dwindling supplies.

The details of Mr Rudd’s online meeting are contained in a letter he sent to Scott Morrison informing the PM he had spoken to Dr Bourla in his personal capacity as a concerned citizen.

The ABC, which obtained a copy of the letter, reports that Mr Rudd stepped in after a senior Australian business figure living in the US also met twice with Pfizer because he despaired of the Coalition government’s vaccine supplies.

The ABC reports that senior Pfizer executives were astonished that Mr Morrison had not directly spoken to the Pfizer chairman and suggested that Mr  Rudd – known to them because of his work in the US – might have some influence.

A network of Australian businesspeople reportedly approached Mr Rudd after learning from Pfizer that the drug company had been offended by the Australian government during early vaccine contract negotiations.

Health Minister Greg Hunt said on Sunday that the recent bringing forward of Pfizer doses was a result of government negotiations with Pfizer Australia.

In Mr Rudd’s letter, he told Mr Morrison that the Pfizer chairman said the company had limited flexibility because of its global supply obligations but Dr Bourla would “personally look ‘at what further may be able to be done’.”

“My understanding was that there were current contractual arrangements with the Australian government to deliver a total 40 million doses by the end of 2021,” Mr Rudd wrote.

“Dr Bourla indicated that they had limited flexibility because of their existing supply obligations around the world. Nonetheless, he also indicated that a number of their manufacturing facilities were producing ahead of schedule.

The first page of Kevin Rudd’s letter to Scott Morrison.

If it was possible for Pfizer to accelerate the doses, Dr Bourla indicated it would need a contractual request from the Australian government, Mr Rudd’s letter states.

“Speaking on my own initiative, I floated the possibility of Australia perhaps seeking a large-scale advance order of Pfizer’s 2022 vaccine ‘booster’ which, from what I have read, is still under development,” Mr Rudd wrote.

“I speculated that it might perhaps be possible for the Australian government to consider a commercial offer for the 2022 booster that would also incorporate a bringing-forward of the current order for the 2021 vaccine into the early part of the third quarter of this year.

“Once again, I emphasised to Dr Bourla that this was speculation on my own part, rather than me acting in any way on behalf of the Australian government.

“As Dr Bourla lives in New York, we also agreed to catch up when I return there later this year.”

On Friday, nine days after Mr Rudd’s Zoom meeting, Mr Morrison announced that Australia’s Pfizer doses would be brought forward, with 1 million jabs a week from July.

“We have been working with Pfizer now for quite some period of time to bring forward our supplies … I commend Minister [Greg] Hunt and Professor [Brendan] Murphy and Lieutenant-General [John] Frewen for the great job getting those supplies brought forward,” Mr Morrison said at the time.

Responding to the ABC’s report on Sunday, a spokesperson for Mr Hunt said the Australian government at all levels had been “proactively and continuously engaged directly with Pfizer throughout the COVID-19 vaccine rollout”.

“As part of this process, the minister has met with the Pfizer Australia country head Anne Harris on multiple occasions with a view to the announcement Friday on the timeframe achieved and at the level we had hoped for, which was the maximum that Pfizer had indicated might be available,” said the statement.

“While we were made aware of Mr Rudd’s approach, we are not aware this approach had any impact on the outcome.

“The Horizons document released in June referred to the expected base of 600,000 doses per week in August up to the one million per week figure which was achieved on an ongoing basis and we thank Pfizer for their continued support.

“We appreciate all contributions from those outside of government, even if they made no material difference to the outcome.”

Pfizer has promised Australia 40 million doses of the vaccine, which will be fast-tracked by several months. The total order will not increase.

Australia has 300,000-350,000 Pfizer vaccines doses a week to administer. That will jump to one million a week in the second half of July.

In August, Australia will receive 4.5 million doses of Pfizer vaccines, significantly more than first anticipated.