Aegon is expected to report a 40% slide in its quarterly profits when it reports its annual results shortly.
The warning comes as large writedowns are belived to be punishing its 2002 results performance. The company has also fallen victim to crumbling stock markets.
The Dutch insurance group is expected to maintain its guidance that full-year profit would slide by a third. According to a Reuters poll of eight analysts, the forecast for profit is £368m euros, a 38% plunge from last year.
JP Morgan said: "We believe (writedowns, defaults and provisions) will hit Aegon's third-quarter earnings, albeit on a smaller scale than in Q2."
