National oil company Petroliam Nasional Bhd (Petronas) keeps mum on its president/chief executive officer Tan Sri Wan Zulkiflee Wan Ariffin's purported resignation after five years at the helm of Malaysia's sole company listed on the Fortune 500.

In response to a query by Bernama, Petronas said it does not comment on market rumour or speculation, that is consistent with its practices.

"Official announcements, if any, will be made at the appropriate time," said Petronas in a statement to Bernama.

According to sources, Wan Zulkiflee or fondly known as Wan Zul's resignation is expected to be announced soon, and his vacant position will be succeeded by an internal candidate.

Wan Zul's contract was renewed for three years from April 1, 2018. It was unclear on the reason why Wan Zul has decided to leave Petronas where he has spent his entire career since 1983.

The news of his possible resignation was also reported by several news outlets since yesterday.

-- BERNAMA