Blackstone Group LP's much-anticipated initial public offering of its management company will occur during the week of June 25, underwriter Morgan Stanley said on Wednesday.

Blackstone, the world's largest private-equity firm, will sell 12.3 percent of its management arm in an offering expected to value the entire company at around $32 billion. Investors will have little voting say in Blackstone itself; instead, their stake would be tied to the management committee that runs the company.

Earlier this week, Blackstone raised eyebrows when it disclosed that Chief Executive Stephen Schwarzman made $400 million in 2006, nearly double the combined compensation for the CEOs of Wall Street's five biggest investment banks.

Schwarzman will control about 24 percent of Blackstone after the IPO.