UEFA is preparing to sanction six Europa League clubs for failing to pay debts on time.

UEFA said Thursday that the clubs are: Skonto (Latvia), Slask Wroclaw (Poland), Vitoria Guimaraes (Portugal), Pandurii Targu Jiu (Romania), Petrolul Ploiesti (Romania) and Metalurg Donetsk (Ukraine).

Punishments could include fines, withholding prize money and suspensions from future Champions League or Europa League competitions.

Only Vitoria and Pandurii remain in this season's Europa League. The Portuguese club is third in Group I led by Real Betis, and the Romanian club is third behind Group E leader Fiorentina.

UEFA said the clubs have been investigated by its Club Financial Control Body, chaired by former Belgium prime minister Jean-Luc Dehaene.

Sanctions are expected to be imposed by the judging chamber next month.

The six clubs were among the 31 identified by UEFA in September as being monitored for overdue payments of wages, transfer fees or taxes.

UEFA said the other 25 cases were closed after clubs met a Sept. 30 deadline to deal with their problems.

Clubs must settle ''overdue payables'' to obtain a license from their national association to play in UEFA competitions.