Umno information chief Annuar Musa has warned presidential candidates Tengku Razaleigh Hamzah and Khairy Jamaluddin over the pitfalls in taking part in a televised debate ahead of the June 30 party polls.

Annuar said while there is a need to be open, the openness should not be detrimental to the objective and strategy of the party's struggle, explaining that the party election is a family affair of Umno and it is subjected to rules, ethics and tradition.