Carol Williams, 61, settled with her husband, businessman John Williams, just two months before the landmark case of White v White, which changed the way divorce cases of the very rich are dealt with.

Mrs Williams says her solicitor and barrister should have advised her about the impending change of the law and waited until after the case rather than accepting the £1.4million award. If she had waited until after the case she claims she would have received a settlement of nearly £3 million.

She is suing the Reading-based solicitors, Thompson Leatherdale, as well as her then barrister, Nicholas Francis QC, for alleged professional negligence and is seeking a further £1.6m from them. Both Mr Francis and Thompson Leatherdale deny liability in the case and claim Mr Francis could not have foreseen the change in the law.