Umno supreme council member Ismail Sabri Yaakob says he hopes the fight between Pakatan Harapan and PAS over the Sungai Besar seat will continue, but the ruling party must not do the same.

"I hope we let them quarrel, but we must be united and strong.

"I hope whatever happens in Sungai Besar, whoever the candidate picked is, we must accept," he said at a press conference at the Persidangan Ayahanda Se Malaysia 2016 at Sultan Sulaiman Club, Kuala Lumpur.

"In an electoral contest, it is not a contest of the individual against the individual, but party against party.

"Our priority must be to make the party win," he added.

He also warned that BN should not rest on its laurels as the opposition may come together at any time.

"Let's not count on the weaknesses of others to win. We must have our own strengths in order to win," he warned.

Harapan and PAS are both eyeing the Selangor seat and calling on the other to back down in order to ensure a straight fight with BN.

However, neither side appears to be willing to give way at the moment.

Today Selangor PAS commissioner Iskandar Abdul Samad repeated his party's determination to contest the seat as their right, calling on other opposition parties not to dispute the matter.

The Election Commission has set June 5 for nominations and polling will be on June 18.

The Sungai Besar and Kuala Kangsar seats fell vacant after the deaths of its incumbents in the Sarawak helicopter tragedy during the state election campaign.