Tech giant Meta apologised Tuesday for removing social media posts by Malaysian Prime Minister Anwar Ibrahim about the assassination of Hamas leader Ismail Haniyeh.

The apology came a day after Anwar's office summoned Meta representatives to seek an explanation on why the leader's Facebook and Instagram posts about Haniyeh's death had been removed.

Meta is the parent firm of the two popular social media platforms.

"We apologise for an operational error where content from the Prime Minister's Facebook and Instagram Pages were removed," Meta said in a statement emailed to AFP.

"The content has since been restored with the correct newsworthy label."

The political leader of Palestinian armed group Hamas was killed in the Iranian capital Tehran on Wednesday in an attack blamed on Israel, which has not directly commented on it.

Anwar's posts included a video showing the premier on a phone call with a Hamas official, offering his condolences.

On Instagram, there was a note by Meta, shared by Anwar, that the posts were taken down because of association with "dangerous individuals and organisations".

Anwar's office had described Meta's removal of the posts as "a blatant suppression of free expression" and demanded an apology from the tech behemoth.

Anwar last week accused the tech giant of "cowardice" for removing his posts.

Israel, the United States and the European Union consider Hamas a terrorist organisation.

Anwar, who met Haniyeh in Qatar in May, has defended Malaysia's ties with the Iran-backed Palestinian militant group, which launched a deadly attack against Israel on October 7 that triggered the war in Gaza.

Anwar stressed during a visit to Germany in March that Malaysia's links were with Hamas' political wing and not with its military arm.