Barclays (>> Barclays PLC), Citigroup (>> Citigroup Inc) and JP Morgan (>> JPMorgan Chase & Co.) will manage the IPO, the sources said, speaking on condition of anonymity.

London's Stock Exchange has seen a flurry of companies rush to list on its markets this year, including estate agent Countrywide Holdings (>> Countrywide plc) and life insurer Partnership Assurance (>> Partnership Assurance Group PLC), as firms look to capitalise on rising equity markets and a recovery in investor confidence.

Budapest-based Wizz Air flies more than 250 routes across Europe and has a fleet of more than 40 Airbus planes.

Rivals Easyjet (>> easyJet plc) and Ryanair (>> Ryanair Holdings plc) are also listed in London.

A spokesman for Wizz Air declined to comment, as did spokesmen for the three banks.

(Reporting by Tommy Wilkes, Clare Hutchison & Anjuli Davies; editing by Patrick Graham)