The leader of Yemen's Shiite Huthi rebels said Friday he did not expect a humanitarian ceasefire to hold, hours before the UN-proposed truce was due to come into effect, demanding an end to Saudi "aggression."

"We do not have much hope for the truce to succeed," said Abdulmalik al-Huthi in a televised statement aired on the rebel Al-Masirah channel, ahead of the truce deadline at midnight.

"The success of the truce depends on the commitment of the Saudi regime and is conditioned to a complete end to the aggression," he added referring to the Saudi-led air campaign in support of exiled President Abedrabbo Mansour Hadi.