Mr Kouwenhoven has denied all the charges
A Dutch court has overturned the acquittal of a man accused of supplying arms to Liberia during the presidency of war crimes suspect Charles Taylor.
The Dutch Supreme Court referred the case of timber trader Guus Kouwenhoven for a new trial.
He is accused of breaking a UN arms embargo by supplying anti-tank weapons and rifles to Mr Taylor's government.
In 2006 Mr Kouwenhoven was sentenced to eight years in jail. In 2008 he successfully appealed and was freed.
Mr Kouwenhoven has always acknowledged close ties with Mr Taylor, but denied any wrongdoing.
On Tuesday, the Dutch Supreme Court said that appeals judges had been wrong to reject a prosecution request to hear the evidence of two new witnesses.
"Under the circumstances, the court should have left the public prosecution more opportunity to have these witnesses heard," it said in a statement.
The date for a fresh appeals hearing is yet to be set.
Mr Kouwenhoven was president of the Oriental Trading Corporation between 2000 and 2003, when the arms smuggling allegedly took place.
His close associate, Charles Taylor, is now on trial in The Hague at a UN-backed court on charges of crimes against humanity and war crimes.
Mr Taylor is accused of backing militias in Sierra Leone who murdered, raped and tortured civilians during the country's civil war from 1991 to 2001.