Belgian prosecutors have demanded a three-year jail term for a former aide to Prince Laurent, the king's youngest son, over alleged embezzlement.
The case has put Prince Laurent in the media spotlight
The retired naval captain, Noel Vaessen, is among 12 people on trial accused of embezzling some 2.2m euros (£1.5m; $2.8m) from the Belgian navy.
Prince Laurent, 11th in line to the throne, has said he knew funds to refurbish his villa came from the navy.
But he told the court on Tuesday that he had not suspected fraud at the time.
He was the first senior Belgian royal ever to testify in open court. The case is being heard in the eastern town of Hasselt.
A former naval officer, Marc Luypaerts, is facing a possible four-year jail term in the case.
Prosecutors have demanded shorter sentences for several more of the accused.
The newspaper La Libre Belgique reports that 1.2m euros (£0.8m; $1.5m) has still not been traced.
Another Belgian paper, Le Soir, says the defence ministry does not plan to claim compensation from Prince Laurent, but from those charged in the fraud investigation.
A Belgian royal spokesman said that if the court decides that the prince benefited, even unintentionally, then he would take note of what his father King Albert II said in his Christmas address - that no-one is above the law, and anyone who profited should pay back the money.