Ismail Sabri Yaakob will assume the duties of Umno deputy president with immediate effect, said the party's secretary-general Annuar Musa.
This is due to the current number two Mohamad Hasan serving as the de facto president following Ahmad Zahid Hamidi's decision to go on leave.
Ismail Sabri was elected one of three vice-presidents in the Umno polls in July. He bagged the highest number of votes compared to the other two – Khaled Nordin and Mahdzir Khalid.
The move to appoint the Bera MP as the party's de facto deputy president came after an Umno management meeting today.
The meeting also agreed to Mohamad taking on Zahid's duties as president.
Zahid had announced that he was handing over the reins to Mohamad on Tuesday night.
He said he would stay on leave until the former Negeri Sembilan menteri besar no longer wanted to carry out the president's duties.
Annuar hoped the new line-up will be able to continue efforts to strengthen the party.
"Umno's priority now is too strengthen its leadership and focus on strengthening the party.
"It is hoped that this process at all levels can be realised as wished by Zahid," he said.
Zahid had stepped aside as Umno president following pressure from other leaders.
This came following continued defections among Umno MPs, with six of them quitting last Friday.