Airline giant IAG, the owner of British Airways and Spanish carrier Iberia, announced Thursday it was cutting more flights because of coronavirus restrictions and quarantine rules.

It comes as IAG said it had raised 2.74 billion euros ($3.23 billion) to help the company navigate through the Covid-19 crisis that has decimated travel demand.

IAG expects to operate 60 percent less capacity in the three months to the end of December from a year earlier. That compared with a previously planned capacity reduction of 46 percent.

The conglomerate blamed the deeper cutbacks on "the impact of current travel restrictions and quarantine requirements on booking activity".

Total 2020 capacity is expected to be 63 percent lower than in 2019 -- down from previous guidance of minus 59 percent.

In response to the global health emergency, the London-listed titan embarked upon a massive jobs-slashing efficiency drive, in line with carriers like Air Canada, American Airlines and Lufthansa.

The European travel giant, whose portfolio also includes Aer Lingus, Level and Vueling, is in the process of axing 13,000 jobs or more than a quarter of its workforce.

"IAG acted quickly to mitigate the impacts of the Covid-19 pandemic, bolster liquidity and to protect its long-term future," it added Thursday.

"The capital increase, together with its quick response to the crisis, should enable the group to emerge from the current pandemic in a strong position."

The company reiterated guidance that it would take until at least 2023 for passenger demand to recover to pre-pandemic levels.