LONDON, May 8 — There is only enough fuel to run health services in the south of Gaza for three more days, the World Health Organisation said today.

Hundreds of thousands of Palestinians have sought refuge in the south of Gaza from combat further north in the enclave. Israel has threatened a major assault on the southern city of Rafah to defeat thousands of Hamas fighters it says are holed up there, and its troops are now battling Hamas on Rafah’s outskirts.