LONDON, July 18 (Reuters) - London's Canary Wharf financial district plans to cut chunks out of one of its tallest office towers once banking giant HSBC moves out, in one of the highest profile redevelopment projects yet to repurpose office buildings since the pandemic.

Qatar's sovereign wealth fund the Qatar Investment Authority (QIA), which owns the 45-floor building, and the area's landlord Canary Wharf Group (CWG), said they planned to reshape the tower to make it more suitable for a mix of uses.

Reuters first reported in May that CWG had asked around 20 architects to come up with alternative plans for the tower, including potentially incorporating hotels and apartments.

Architects Kohn Pedersen Fox (KPF) won the design contest, CWG said on Thursday, with visualisations published showing large voids will be cut into the building to split it up and provide large outdoor terraces. CWG said the plan was to attract leisure, entertainment, education and cultural uses as well as office space. Construction work will begin in 2027.

Construction trade magazine Building first reported KPF had won the contest.

HSBC decided last year to quit the skyscraper sporting its name in late 2026, moving to a building half its size in the more central City of London district.

The fate of one of Britain's biggest office buildings is being closely watched by a property industry pummelled by high borrowing costs and changing post-pandemic work patterns.

QIA's investment to overhaul 8 Canada Square was a "flagship example of the sovereign fund's vision for multi-use real estate of the future", CWG said in a statement.

Canary Wharf has seen several high-profile tenants announce their departure from the estate on London's former docklands, although others including banks Barclays and Morgan Stanley have committed to stay.

CWG has sought to diversify the area beyond office working, and said visitor numbers hit at an all-time high of 67.2 million during 2023.

The group said in April that property values in the area had fallen by 15%, or 1.2 billion pounds ($1.6 billion), in a year.

It did not disclose the estimated cost of the tower revamp.

A source familiar with CWG's thinking previously told Reuters it could run into hundreds of millions of pounds.

($1 = 0.7702 pounds) (Reporting by Iain Withers; Editing by Tommy Reggiori Wilkes and Mark Potter)