The Canary Wharf Group is planning a huge new speculative building project in its Docklands estate, at the same time as eyeing up building opportunities in Central London, including the redevelopment of Bucklersbury House, the City’s largest new scheme for 25 years.

George Iacobescu, chief executive of Canary Wharf Group, told The Times that the company would build a 32,500 sq m tower block speculatively – without a tenant prelet in place – at 25 Churchill Place.

The new building could rise to 15 storeys and sell for about £300 million based on recent, similar-sized schemes on the estate.

Canary Wharf has already started work to lay the roads and foundations for the Churchill Place site and another scheme for 167,000 sq m of buildings at Riverside South, just south of Westferry Circus.

Meanwhile, Canary Wharf has set up a property joint venture to examine bids for City and South Bank office schemes.

One site on the Wharf’s radar is Walbrook Square near Mansion House, all-owned by Legal & General (L&G), according to Richard Archer, Canary Wharf’s head of leasing. The 1.5hectare site covers both Bucklersbury House and Temple Court, which L&G wants to knock down and turn into four closely aligned buildings rising at the highest point to 107m and each topped with shimmering glass edifices, which the designers call “the clouds”. The offices will cover 158,000 sq m set among shops and cafés. Once built and let, Walbrook could be worth £1.25 billion.

L&G is due to vacate Walbrook this autumn for a new headquarters and is thought to be examing whether to sell or develop Walbrook with a partner.

Canary Wharf’s plans are based on its conviction that London will surge ahead of New York as the world’s leading international financial centre over the next two decades. That in turn, it is thought, will create even more demand for jobs and buildings to house them.

Docklands, Mr Iacobescu said, should more than double its workforce to over 200,000 during the next two decades, while he believes that the City’s workforce will grow from 300,000 today to 400,000 by 2026.

Canary Wharf Group, a company that is part-owned by Morgan Stanley Real Estate Fund (MESREF) and the FTSE 100 developer British Land, is intent on capitalising on growth prospects both in Docklands and Central London. Canary Wharf has formed a joint venture with the privately-owned Exemplaar Developments and with MESREF to build a 14-storey, 28,000 sq m City office block at Drapers Gardens.

Mr Archer said: “Drapers Gardens was our first foray into the City and we are looking at more opportunities to take that venture into Central London. There are three or four schemes of three to four million sq ft [280,000-370,000 sq m] in total. There is Walbrook Square – the Legal & General scheme – where planning is due in September. There is also Waterloo.”

Any building in Waterloo is likely to be on a site currently owned by P&O Estates and MESREF. Last month, they submitted plans for a 133,000 sq m redevelopment of Elizabeth House next to Waterloo Station comprising one 28-storey and one 22-storey office block and a 54-storey residential tower.

Property sources said Canary Wharf is also keen on bidding for Shell Centre on the South Bank. This 2.2hectare site could be turned into a 102,000 sq m complex. Royal Dutch Shell has lined up CB Richard Ellis, the agents, for a possible sale of the site.

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