Travel recovery from Covid-19 could take two years or more, Delta Air LInes has warned.

The projection came as the US carrier disclosed an average daily cash burn of $24 million a day in the three months to September and $18 million a day during last month.

The US partner of Virgin Atlantic reported a quarterly pre-tax loss of $2.6 billion, excluding $4 billion directly related to the impact of the pandemic, including fleet restructuring and staff early retirement and lay off costs.

Part of the outlay was covered by a $701 million government bailout. The September quarter amount included an incremental $157 million beyond an initial $5.4 billion Delta was allocated in April.

Revenue in the summer three months of $2.6 billion was down 79% on 63% lower capacity over the same period in 2019 as demand for air travel remained under “significant pressure”.

The airline had $21.6 billion in liquidity at the end of the quarter.

Delta plans to accelerate the retirement of nearly 400 aircraft by 2025, including more than 200 this year.

President Glen Hauenstein said: “With a slow and steady build in demand, we are restoring flying to meet our customers’ needs, while staying nimble with our capacity in light of Covid-19.

“While it may be two years or more until we see a normalised revenue environment, by restoring customer confidence in travel and building customer loyalty now, we are creating the foundation for sustainable future revenue growth.”

Chief executive Ed Bastian said: “While our September quarter results demonstrate the magnitude of the pandemic on our business, we have been encouraged as more customers travel and we are seeing a path of progressive improvement in our revenues, financial results and daily cash burn.

“The actions we are taking now to take care of our people, simplify our fleet, improve the customer experience, and strengthen our brand will allow Delta to accelerate into a post-Covid recovery.”