US buy-out group Kohlberg Kravis Roberts (KKR) has made an offer of up to A$1.75bn ($1.73bn) to buy Australian investment groups Perpetual.

The offer values each Perpetual shares at A$38 to A$40 each, which represented a 22% premium to 15 October 2010 close at the lower end of the range.

Perpetual board hasn’t dismissed the offer yet.

Last month, Pepetual Investments reported funds under management of $27.5bn, down from $27.7bn in July. Perpetual’s performance has been lacklustre for some time.