The Cochin International Airport will reopen on August 29, news agency IANS reported.
The airport was shut on August 15 due to massive floods that wreaked havoc in the state.
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On Tuesday, the airport had said that it would resume operations on August 26.
According to officials, the opening had been put off by three days as 90 per cent of the staff had been affected by Kerala's worst flooding in a century and they needed to report to work.
The airport was closed on August 15 after it was flooded when various dams in Idukki district opened their sluice gates in the wake of torrential rains.
The airport was first closed on August 9, for a few hours, and then on August 15. The Cochin airport is one of three airports in Kerala and also the busiest.
(With IANS inputs)