By Marietta Cauchi Of DOW JONES NEWSWIRES LONDON (Dow Jones)--U.S. buyout firms TPG and Blackstone Group (BX) and London-based Apax Partners are among potential bidders for Polish mobile phone operator Polkomtel, people familiar with the situation said Friday. Polkomtel has a handful of shareholders, mainly former communist-era conglomerates, that had been considering a listing of Polkomtel on the Warsaw Stock Exchange, but have now opted for a private sale. Information memorandum are expected to be circulated by the end of August, or perhaps even sooner, with a closing potentially in 2010 or the first quarter of 2011, one person has previously said. The company is worth about 16 billion zlotys ($4.86 billion), according to analysts, and some of its shareholders are keen to divest non-core assets to be able to invest in their main businesses. Polkomtel is owned by five companies, three of which have hired banks to advise them on selling their stakes. Poland's largest power group PGE (PGE.WA) holds a 21.85% stake and is advised by ING Securities. Oil refiner PKN Orlen SA (PKN.WA) holds 24.39% and is advised by Nomura. Copper miner KGHM Polska Miedzy (KGH.WA) holds 24.39% and is advised by Credit Suisse. Poland's Treasury owns stakes of 84.99%, 27.52%, and 31.79%, respectively, in the three companies. Coal miner Weglokoks SA, which is wholly Treasury-owned, holds a 5% stake in Polkomtel. Vodafone Group PLC (VOD.LN) also holds 24.39% of the firm, but hasn't publicly revealed its strategy toward Polkomtel. -By Marietta Cauchi, Dow Jones Newswires; +44 207 842 9241; marietta.cauchi@dowjones.com (Marynia Kruk contributed to this article.) (END) Dow Jones Newswires July 02, 2010 10:57 ET (14:57 GMT)