UPDATE 1-Angola and Congo tell dos Santos to cooperate with justice after asset freeze

Sergio Goncalves and Catarina Demony

asset freeze@ (Adds information, background)

LISBON, Jan 5 (Reuters) - The presidents of Angola and Congo said on Sunday Isabel dos Santos, the billionaire daughter of Angola's previous leader and her Congolese husband Sindika Dokolo, should cooperate with the justice system after their assets were frozen.

In a statement, the presidents said the best way forward for dos Santos and Dokolo, as well as Mario Leite da Silva, chairman of Banco de Fomento Angola (BFA), was "maximum cooperation with the competent authorities of the state and the Angolan court".

They are yet to react to the presidents' comments.

Angolan president Joao Lourenco and Congo's president Felix Tshilombo met on Sunday in the Angolan city of Benguela, the statement said.

A court document dated Dec. 23 said the government believed dos Santos, Dokolo and Silva had caused the state losses of more than $1 billion.

The asset freeze applies to personal bank accounts of dos Santos, Dokolo and da Silva in Angola and stakes they hold in Angolan firms including Unitel, BFA and ZAP MIDIA.

Dos Santos and her husband have denied the accusations, calling them "politically motivated". Silva has declined to comment. (Reporting by Sergio Goncalves and Catarina Demony; editing by David Evans)