Delta will continue to block the use of middle seats on its flights through to March 30, 2021.

The US carrier introduced the social-distancing measure in response to passenger concerns over the spread of Covid-19 as its first flights resumed.

The policy had been extended until January 6 alongside other anti-Covd protocols such as sanitising, Covid testing of crew, use of HEPA filters

Chief customer experience officer Bill Lentsch said “several independent studies have validated the effectiveness of” Delta CareStandard protocols which he said “significantly reduce the risk of flight-related transmission”.

Lentsch added: “However, we recognise some customers are still learning to live with this virus and desire extra space for their peace of mind. We are listening and will always take the appropriate steps to ensure our customers have complete confidence in their travel with us.”