Umno Youth chief Khairy Jamaluddin said the wing's campaign for the upcoming twin by-elections will not be affected even if former prime minister Dr Mahathir Mohamad decides to go out on the stump against the BN.

"Whether he campaigns or not will not change Umno Youth's plans. We have our own plan and BN in general also has its own plan.

"We do not look at who will be fighting us or who will be campaigning against us, we only focus on our plans," he told a press conference at the Umno headquarters in Kuala Lumpur today.

He was responding to the possibility of Mahathir campaigning against BN in the Sungai Besar and Kuala Kangsar by-elections.

Asked about Mahathir's call for voters to reject BN in the by-elections, Khairy said it was up to voters to decide.

"We do not care about the problems of our opponents or who will be campaigning for them.

"It is up to voters to evaluate who is the best candidate; we will not dance to the tune of the opposition or Mahathir, we will only focus on our work," he said.

Khairy added that BN would not resort to using aggressive tactics which he accused the opposition of doing.

The Sungai Besar and Kuala Kangsar parliamentary constituencies fell vacant following the deaths of the incumbents in a helicopter crash early this month.

The by-elections have been fixed for June 18.