UPDATE 3-KKR extends KPE deadline, listing plans delayed

* Pair still evaluating transaction

* KKR's U.S. stock listing plans rest on the deal

* Seeks extra $730 mln euros for European fund-source (Adds details from story about European fund in paragraph 2, 17 to end; industry background; analyst comment)

By Megan Davies

NEW YORK, April 24 (Reuters) - Private equity firm Kohlberg Kravis Roberts & Co [KKR.UL] on Friday extended by four months the deadline to buy its Amsterdam-listed fund KPE (KKR.AS), a deal that is key to KKR's plans for a U.S. stock listing.

The firm has also asked investors in one of its European funds for an additional 730 million euros ($970 million) to make follow-on investments in the fund's portfolio companies, a source familiar with the plan said on Friday. [nN24411770]

The private equity industry has been struggling with numerous problems -- absence of leverage for new deals, troubled portfolio companies and investors hurt by equity market falls.

New York-based KKR, co-founded by "buyout king" Henry Kravis, has the added problem of having announced plans to take itself public just prior to the markets plunging.

KKR's plans to become a publicly traded company hinge on the deal to buy the KPE fund. If that transaction is scrapped, the listing would be thrown into question.