The demands are part of a legal dispute over a convertible loan extended by Carlyle Global Infrastructure Fund in 2021. Convertible loans are a form of debt that can be transformed into a company's shares under certain conditions.

Carlyle, which last year launched legal action over an alleged breach to the convertible loan agreement, has now requested payment of 193.75 million pounds ($246.88 million) by Feb. 16, Esken said.

Esken said an acceleration of the debt repayments would be "value destructive" to all stakeholders and is focused on finding a new owner for the airport.

Representatives for Carlyle were not immediately available for comment.

($1 = 0.7848 pounds)

(Reporting by Pablo Mayo Cerqueiro; Editing by Kirsten Donovan and Louise Heavens)