A Swiss court has ruled that the assets of late Congolese dictator Mobutu Sese Seko must be returned to his family.

The federal criminal court on Tuesday rejected an appeal to extend a freeze on his assets in Switzerland worth about $7 million, saying the case is now too old.

The decision, which cannot be appealed, brings an end to years of wrangling over the money kept in Swiss bank accounts.

The Swiss foreign ministry said the money will soon be released to Mr. Mobutu's heirs, without specifying the date. 

The assets were frozen in 1997 at the request of the Democratic Republic of Congo's (DRC) government, which says the money was stolen.

The appeal was filed by Swiss professor and anti-corruption activist Mark Pieth, who says that Mobutu's family members were involved in criminal activity.

Pieth said the decision is a setback for the DRC and all those who have fought for the return of the funds.

For much of Mobutu's rule, the country was known as Zaire.  Congolese leaders restored the old name soon after his ouster in 1997.  Mobutu died later that year.

Mobutu came to power in a 1965 coup.  His 32-year rule was marked by economic crisis and state corruption. 

Some information for this report was provided by AFP and AP.