The ceasefire was reached last week in Stockholm after a round of UN-sponsored talks -- the first direct talks in more than two years between representatives of Yemen's internationally recognized government, which Saudi Arabia supports, and the Iranian-backed Houthi rebels.

The December 13 agreement stipulated an immediate ceasefire in Hodeidah, a major flashpoint in the country's war. The besieged rebel-held port city is an entry point for 70% of foreign humanitarian aid into the country, according to the United Nations, which has described Hodeidah as a "lifeline" for Yemen's war-ravaged population.

The agreement also includes mutual withdrawal of military manifestations from the city, redeployment of local forces and deployment of UN monitors for the ports.

"We welcome the announcement of the ceasefire announced by the UN envoy this night, which will take effect shortly, and we affirm that peace is the first option since the very first moment," Mohammed Ali al-Houthi, head of the Supreme Revolutionary Committee of the Iranian-backed Houthi militias, said on Twitter.

International pressure intensified for a ceasefire as the humanitarian crisis worsens in Yemen after more than three years of war.

The war in Yemen has devastated the country and provoked extreme starvation, most notably among the country's children. Some 85,000 children under the age of five may have died there since 2015, according to Save the Children, the international childrens' relief organization.

The talks, which began on December 6, were hailed as a step toward peace in the region. Then, over the weekend, clashes broke out in Hodeidah between Houthi rebels and pro-government forces backed by the Saudi-led coalition. Both sides blamed the other for the clashes in statements made to CNN.

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