Judges rejected a last-minute protest from former Liberian ruler Charles Taylor, clearing the way for British fashion model Naomi Campbell to testify at his war crimes trial on Thursday.
The reluctant Campbell has been subpoenaed to testify about a diamond Taylor allegedly gave her after a dinner party hosted by Nelson Mandela in South Africa in 1997.
Taylor's lawyer, Courtenay Griffiths, had argued that Campbell should not appear until prosecutors provide a summary of her likely testimony.
But judges rejected that in Wednesday's ruling, saying it was not reasonable to expect prosecutors to obtain a statement beforehand from Campbell, who is essentially a hostile witness.
Prosecutors say that if Taylor really gave Campbell the diamond, it would help show he received diamonds from Sierra Leone rebels in exchange for weapons during Sierra Leone's 1992-2002 civil war.