(Adds Treasury comment, details on offer)
SYDNEY, Aug 4 (Reuters) - Kohlberg Kravis Roberts & Co LP has raised its bid for Australia's Treasury Wine Estates to $3.15 billion, the world's No.2 winemaker said on Monday, adding it would grant the private equity giant access for due diligence.
Treasury said KKR and Rhone Capital LLC had raised their bid by 10.6 percent to A$5.20 per share from the A$4.70 offered in April.
Treasury, which owns the Penfolds, Wolfblass and Beringer brands, rejected that bid as too low in May after KKR began approaching investors directly.
"The board of TWE, together with its advisers, has concluded, based on the revised proposal, that it is in the interests of its shareholders to engage further with KKR and Rhone," Treasury said in a statement. It would allow the bidders to conduct "non-exclusive due diligence" subject to a confidentiality agreement.
Treasury shares closed at A$4.95 on Friday.
Treasury's shares have fallen from an all-time high of A$6.43 a year ago amid slashed earnings forecasts, oversupply problems in its U.S arm and sluggish sales in China.
Treasury's problems are reflected in the broader Australian wine industry which has struggled through volatile market conditions and a high currency in recent years.
Under new chief executive Michael Clarke, Treasury has been restructuring to try to improve its performance, separating its Australian luxury and mass prestige portfolio.
(Reporting by Lincoln Feast; Editing by Sandra Maler and Stephen Coates)