KKR Private Equity Investors LP on Friday launched a consent solicitation, seeking approval of its unitholders to proceed with the planned combination with private equity firm Kohlberg Kravis Roberts & Co (KKR).

Combining the two firms is a roundabout way for KKR to gain a European listing, and is a step towards it following rival private equity firm Blackstone Group in becoming a New York Stock Exchange-listed company.

Under the consent solicitation, if the majority of the unitholders provide valid consent prior to the August 14 expiry date, KPE may then move ahead with the proposed plan. Those owning 44 percent of KPE's outstanding shares have agreed to the deal.

Provided that consent is obtained from unitholders, the deal is expected to occur on October 1. The record date for determining which KPE unitholders were entitled to consent to the transaction was July 23.

KKR has had a long, complicated road towards a public listing. Initially KKR launched plans to list on the New York Stock Exchange via a traditional initial public offering in July 2007, a month after Blackstone went public and just before the markets started to tumble.

It later proposed a more complex method of going public, by combining with KPE, delisting the fund from Amsterdam and listing in New York. In June, it formally withdrew the proposed New York IPO plan, but kept the door open for such a move, saying it had the ability to seek a listing in the future.

On Monday, KKR and KPE moved a step closer to merging after receiving approval from the board of the fund to combine businesses.

(Reporting by Jessica Hall; Editing by Derek Caney)