
Hassan, who is a member of Prime Minister Dr Mahathir Mohamad’s Council of Eminent Persons, also served as Petronas CEO from 1995 until his retirement in 2010.
He is chairman of Sembcorp Marine Ltd and senior international adviser at Temasek International Advisors.
Speculation of his return to Petronas began after the Edge Markets reported last week that Sidek and remuneration committee chairman Mohd Omar Mustapha were expected to quit.
Sidek, 67, a former chief secretary of the government, has been chairman of Petronas since July 1, 2012.
He was also the chairman of the Royal Commission of Inquiry appointed by former prime minister Najib Razak to investigate the foreign exchange losses of Bank Negara in the 1990s.