Investment group Blackstone is on course to set the high water mark in the exuberant round of private equity fundraising after saying it had attracted a record $15.6 billion (€12.2 billion) for what is now the world's largest fund.

The New York-based group has in 12 months scooped $30 billion from investors for a range of vehicles, including real estate, corporate debt and hedge funds - only $2 billion short of the amount raised in its previous 19 years of operation.

Kohlberg Kravis Roberts (KKR) is yet to finalise its latest buyout fund, which could attract more than $15 billion. However, KKR recently sold shares worth an additional $5 billion after launching an Amsterdam-listed investment vehicle.

Stephen Schwarzman, Blackstone chief executive, said more than one-quarter of the new BCP V buyout fund, or more than $4 billion, was already at work.

"There is no money burning a hole in our pocket," he said. Blackstone has recently committed equity of $700 million - $1 billion in each of four deals - a stake in Deutsche Telekom and buyouts of media group VNU, arts and craft retailer Michaels Stores, and travel services business Travelport. "We have a significant backlog [ of deals], but we have also turned down a lot of things either because we didn't like the company or the price."

Mr Schwarzman warned that Blackstone and others needed to be careful about prices being paid for companies because "the cycle has got a little ripe".

There has been a steady stream of successively larger buyout funds this year. Texas Pacific Group raised close to $15 billion, while Permira will soon reach an €11 billion target. Last week, Carlyle said it had raised $1.9 billion for a Japan fund, lifting to $17.3 billion the total raised from a suite of private equity funds.

Blackstone revised its fund target at least twice. Earlier this year it was about to close on $13.5 billion, after initially setting a soft target of $10 billion. That move was delayed after news leaked that TPG was seeking $14 billion.