Umno leaders have been advised to watch their words and action because it might adversely impact the party's image.
Cheras Umno chief Syed Ali Alhabshee said this is important as voters are now watching Umno leaders very closely.
"The people, especially youths, are watching the actions of politicians, including from Umno. Bad behaviour will leave a bad impression," he said.
Syed Ali said this will hurt Umno in the 14th general elections.
"Things get more complicated when the rakyat not only condemn the credibility of the Umno leader (who behaved poorly) but direct their hate and anger towards the top Umno leadership," he said in a blog posting.
"We don't want the actions of Umno leaders which are scorned by the rakyat to be blamed on (Umno president) Najib (Abdul Razak). This is unfair and a burden to the party," he said.
Syed Ali also urged all party leaders to be aligned to Najib and refrain from making unbecoming public statements.
This comes after Sungai Besar Umno division chief Jamal Md Yunos was arrested following an unathorised raid on an alleged gambling den in Selangor.
Meanwhile, the Federal Territories BN treasurer urged parties to be more proactive in approaching non-Malay youth voters, so that the voters will better understand BN's aspirations.
He said this is as youths are more inclined to believe "perceptions played up by the opposition" on social media.
Separately, Syed Ali said PAS' decision not to align with Pakatan Harapan should be respected.
He said it shows there is a split in opposition support among Malay voters, with some backing PAS.
"It would be a good development if PAS and Umno can combine on political policies for the sake of Islam, but this is up to the parties' top leaders," he said.- Mkini