VIENNA, Nov 9 (Reuters) - Banks in Austria had 2.2 billion euros ($2.35 billion) in exposure in mid-2023 to indebted property and retail giant Signa Group, owner of New York's Chrysler Building and Britain's Selfridges store, a person with knowledge of the matter said.

Raiffeisen Bank International (RBI) and UniCredit's Bank Austria accounted for two-thirds of this, said the person, who spoke on condition of anonymity.

The exposures, which have not been previously reported, shed some light on the financial links of Signa, which has been a major player in Europe's property industry for more than two decades.

RBI, which the person said had sharply reduced its exposure to the Signa group in recent years, declined to comment on Thursday. UniCredit also declined to comment on its exposure.

Signa did not immediately respond to an email seeking comment on Thursday. The European Central Bank (ECB), which supervises the banks, declined to comment.

On Wednesday, Signa said that Rene Benko would relinquish chairmanship of the company he founded and that it had brought in a restructuring expert to review its asset portfolio.

For years, the European real estate sector boomed as interest rates remained ultra-low, but a sharp rise in rates and building costs has driven some developers into insolvency as bank financing dries up, deals freeze and prices fall.

In recent weeks, Signa's sports retailer filed for insolvency and construction on a skyscraper was halted after the developer stopped paying its builder. Credit rating agency Fitch downgraded one Signa division to junk.

Benko, who remains Signa's largest shareholder, said on Wednesday he was certain it had "a very bright future".

Dozens of banks, insurance companies and pension funds have over the years financed and invested in Signa companies, bond sale prospectuses and a Signa presentation seen by Reuters show.

The financial links are especially strong in Austria, where Signa was founded and is headquartered.

Raiffeisen Landesbank Niederoesterreich-Wien, Raiffeisen Landesbank Oberoesterreich and Erste Group are also among the banks with exposures to Signa, the person said.

Erste said its "commercial real estate portfolio is really very sound". The other two Austrian banks declined to comment.

Banks decided to reduce their exposures after discussions with ECB supervisors, who are worried about Signa's prospects, another person with knowledge of that matter said.

A spokesperson for Austria's central bank said it had no concerns about the country's financial stability, when asked about Signa's financial position.

Austria's National Bank and its Financial Market Authority said they do not comment on individual institutions.

Signa has appointed consultants to help it conduct "a thorough review of all business areas, developing measures and drawing up an integrated concept for the group".

Restructuring expert Arndt Geiwitz who has taken on Benko's role said this week: "Signa needs calm and order at this time". ($1 = 0.9359 euros)

(Additional reporting by Francesco Canepa; writing by Tom Sims; Editing by Elisa Martinuzzi and Alexander Smith)