By Elvira Pollina

MILAN, Dec 19 (Reuters) - Italy's Treasury has agreed to sell PagoPA, which handles digital payments to public administrations, to the state mint and to state-backed postal group Poste Italiane PST.MI for up to 500 million euros ($586 million), the mint said on Friday.

The deal has raised concerns among Italian banks in recent months, as it could boost competition for smaller lenders already struggling to keep pace with rapid changes in the payments sector.

The 500-million-euro valuation includes variable components and future payments, the mint said, without giving further details.

Sources previously told Reuters that lenders had voiced concerns to the Treasury that Poste could use PagoPA to strengthen its position in digital payments, where it already has a significant presence, competing directly with banks.

In a bid to address the concerns raised by the banks but also by Italy's antitrust authority, the deal hands 51% of PagoPA to the mint, while Milan-listed Poste will own the remaining 49%.

Banks are also facing growing competition on payments from global tech players such as Apple AAPL.O, Google-owner Alphabet GOOGL.O and PayPal PYPL.O.

Poste has evolved into a financial conglomerate, expanding beyond its core postal business into payments, mobile services, energy supply, insurance and investment products.

PagoPA, which processed 97 billion euros in payments to Italy's public administration this year, is expected to play a key role in Rome's plan to develop a digital wallet through the IO mobile app.

The app allows Italians to store official documents, including digital identity credentials, and make payments to public entities.

($1 = 0.8534 euros)

(Reporting by Elvira Pollina; Editing by Valentina Za)

((giuseppe.fonte@thomsonreuters.com; +390680307711;))