AMP has so far been unable to sell its private markets business to US-based Ares Management Corporation, after a preliminary agreement lapsed.
The wealth manager on Monday said a 30-day heads of agreement with Ares to sell AMP Capital's markets business had concluded.
The two businesses continue working on a sale.
In October, Ares offered to buy AMP but talks fell through. The two later tried for a joint venture on the markets business.
The sale setback comes after AMP on Friday denied media reports that chief executive Francesco De Ferrari resigned.
The company said the board and Mr De Ferrari were discussing future leadership.
AMP has been reviewing its operations since last year in view of increased unsolicited offers for parts of the business.
The business on Monday also said it was ending its management agreement with real estate investment trust, Precinct Properties New Zealand.
AMP will sell its management interests for $197 million.
Shares were down 0.56 per cent to $1.33 at 1126 AEDT.