LONDON (Reuters) -Blackstone is among several bidders shortlisted to buy a more than century-old office block in Paris with a price tag of 700 million euros ($800 million), a source familiar with the matter told Reuters, in what would be one of Europe's biggest post-pandemic office sales.

The CityQuartier Trocadéro building is in a prime location in the 16th arrondissement near the Arc de Triomphe and was put up for sale by the owner, Germany's Union Investment, in March.

Real estate investor Hines also made the cut, while Commerz Real, owned by Germany's Commerzbank, also put forward a bid that was unsuccessful, separate sources said. All sources declined to be named citing the sensitivity of the process.

Global office prices were crushed after the COVID-19 pandemic upended working patterns, but return-to-office mandates have started to improve the picture, with investors warming to buildings seen as trophy assets in desirable locations.

Built in 1913, the 444,000 square feet Paris block also contains 57 luxury apartments, catering and cafes. It was originally owned by French bank Societe Generale before being sold to Union in 2003.

Investors have submitted bids in recent days, with some coming in under the asking price and closer to 650 million euros, the first source said. The process is still live and there can be no guarantee a deal is reached.

A spokesperson for Union Investment confirmed that it had shortlisted investors and said it had excluded offers below 650 million euros. It declined to comment on individual bidders.

Blackstone, Hines and Commerz Real declined to comment.

Property publication Green Street News first reported that bidders had been shortlisted, and that others included AXA IM, Tishman Speyer and a joint venture between Norges Bank Investment Management (NBIM) and Generali.

NBIM declined to comment, while the other investors named by GSN were not immediately available for comment.

The building's offices are 98% let and home to tenants including watchmaker Swatch Group, chocolatier Lindt & Sprüngli and law firm Reed Smith.

Office sales in Europe last year slumped to their lowest level since 2009 and transaction levels have remained subdued this year, according to MSCI data.

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