Luton Airport looks set to be sold for around £400m.
The airport handled 9.6 million passengers last year and will be, subject to regulatory approval, Aena's fifth largest airport.
Aena executive chairman Jose Manuel Vargas said: "We aim to substantially build up Luton in consultation with all its stakeholders."
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Showers this evening, dying out overnight.
The Bishop of Norwich has called for unity and calm in the wake of the referendum vote to leave the European Union.
Showers becoming heavy this afternoon, with thunder possible.