BEIRUT- Saudi Aramco Chief Executive Amin Nasser said on Thursday the energy transition "was not going smoothly", pointing to a resurgence in demand for oil and gas as the global economy recovers while supplies lag on the back of falling investment.

"We all agree that to move towards a sustainable energy future a smooth energy transition is absolutely essential but we must also consider the complexities and challenges to get there," he told the B20 conference in Indonesia via video link.

"We have to acknowledge that the current transition is not going smoothly," he said.

(Reporting By Maha El Dahan and Nadine Awadalla; Editing by Kirsten Donovan) ((; + 9712 4082101; Reuters Messaging: