United Nations Secretary-General Antonio Guterres made a rare move on Wednesday to invoke Article 99 of the UN Charter.
It allows the secretary-general to draw the attention of the Security Council to "any matter which, in his opinion, may jeopardize the maintenance of international peace and security."
It is the first time since Guterres took office in 2017 that he has made such a move. According to the UN, Article 99 has not been invoked for decades.
The enormous loss of life in the Gaza Strip and Israel within a comparatively short period was the main factor behind the decision, the UN said.
In a letter shared on X, formerly Twitter, Guterres wrote: "I urge the members of the Security Council to press to avert a humanitarian catastrophe. I reiterate my appeal for a humanitarian cease-fire to be declared. This is urgent."
There are no direct consequences of invoking Article 99. However, the Security Council is expected to meet on Thursday or Friday to discuss the issue, a meeting in which Guterres is set to attend.