Umno issued a show-cause letter to its member Yammy Samat today for backing her daughter Dyana Sofya Mohd Daud's candidacy in the May 31 Teluk Intan by-election under the DAP banner.

"I have written a show cause letter to her asking why she should not be suspended or sacked from Umno for her actions in the Teluk Intan by-election," Umno secretary-general Tengku Adnan Tengku Mansor told journalists in Kuala Lumpur this afternoon.

"In the letter, I also said we are aware that the candidate (contesting against BN) is her daughter, but the party has its discipline," he added.