QSuper, which already owns an 11 per cent stake in London’s Heathrow Airport, joined with a group of investors led by IFM to make an offer for the airport at $8.25 for each stapled security.

The bid would expose QSuper’s large number of public service members to another airport in the middle of a pandemic when Australia’s international borders are closed and domestic travel is impacted by COVID-19 restrictions.

The bid was unsolicited, indicative and conditional as well as non-binding and below where the airport’s securities were trading before the pandemic.

“The indicative proposal has been made during a global pandemic which has deeply affected the aviation industry and the Sydney Airport security price,” the airport said.

The board of Sydney Airport has also said it believed the impact of the pandemic would be short term.

However, the offer is more than 40 per cent above the closing price for Sydney Airport’s shares on Friday, but its shares jumped 33 per cent at the open of the market this morning.

It said the board was carrying a detailed analysis of whether the proposal was reflective of the underlying value of the airport given the impact of the pandemic.

The conditions of the bid include that UniSuper, which currently holds 5 per cent of Sydney Airport, agrees to reinvest through the consortium.

Due diligence also has to be completed and the airport must also recommend to investors to vote in favour of the deal.

Although a large number of public servants invest through QSuper, it became an open fund in 2017.

It is currently negotiating a merger with Sunsuper.