London: Brookfield Asset Management Inc, owner of a stake in the UK's tallest building, is about to start constructing an even higher tower in the City of London.

The 64-storey Pinnacle is currently the only major office project scheduled for completion after 2012 in the City, the capital's main financial district.

That may be about to change.

Brookfield is seeking a site to build another office tower, this time as developer. Land Securities Group Plc, the UK's largest real estate investment trust, is preparing to revive a skyscraper project it shelved two years ago.

City of London real estate is becoming attractive again to companies like Toronto-based Brookfield after the worst recession on record stopped most development. A shortage of prime office space may push rents back to their 2007 peak in three years, according to King Sturge, a London-based broker. That's encouraging other companies to follow Brookfield's lead.

"I'm not surprised that developers are sharpening their pencils again," said Savvas Savouri, head of research at BH2, another broker based in the city. "The issue now is supply of space, not demand."

Brookfield's construction workers are sealing the foundations of the Pinnacle, a tower commissioned by investors based in Saudi Arabia. When it's finished, the building will have a height of 288 metres, 53 more than the skyscraper in the Canary Wharf district that holds the UK record.

The company's development unit has seen some "interesting opportunities" for an office building in the City of London, according to James Tuckey, chairman of Brookfield's European arm.