RIYADH, Saudi Arabia (AP) — Saudi Arabia's energy minister says the head of the kingdom's sovereign wealth fund is replacing him as chairman of the board of Saudi Aramco as the state-run oil giant plans an initial public offering.

The move puts some distance between Khalid al-Falih's energy ministry portfolio and Aramco, which Saudi officials say could be listed in 2020 or 2021.

Al-Falih described Yasir al-Rumayyan's appointment on Twitter Monday as "an important step to prepare the company for a public offering."

Crown Prince Mohammed bin Salman first announced plans for a partial IPO in 2016. The world's most profitable company plans to list in Saudi Arabia and on an international exchange.

Al-Rumayyan, who is managing director of the Saudi Public Investment Fund, served on Aramco's board prior to becoming its chairman.