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SYDNEY, April 19 (Reuters) - A consortium backed by U.S. private equity firm KKR & Co KKR.N offered A$6.15 billion ($4.65 billion) cash for Australian lottery operator Tatts Group Ltd TTS.AX , threatening an agreed merger with Tabcorp Holdings Ltd TAH.AX , two sources familiar with the situation said on Wednesday.
The sources, who were not authorised to speak publicly, told Reuters a letter offering A$4.21 a share had been sent to the Tatts board on Tuesday evening.
Representatives of Tatts, Tabcorp and the KKR-backed Pacific Consortium declined immediate comment.
Tatts in October agreed to accept a cash-and-scrip proposal from betting group Tabcorp to form an Australian gambling powerhouse. shares closed at A$4.35 a share on Tuesday. The Tabcorp offer, which has yet to receive competition approvals, values Tatts shares at A$4.21 based on Tabcorp's closing price on Tuesday.
The Pacific Consortium, which in December made a takeover offer rejected by the Tatts board, also includes Macquarie Group, Morgan Stanley (NYSE:MS) Infrastructure and First State Superannuation Scheme. in November purchased a 9.9 percent stake in Tatts to make it harder for an interloper to block their agreed merger. = 1.3226 Australian dollars)