The July 20 attack on the western port city of Hodeida, controlled by Yemen's Houthis, came a day after the rebels claimed responsibility for a drone attack on Israel's commercial hub of Tel Aviv, killing one person.

The Israeli attack decimated the Hodeida port's fuel storage capacity and killed at least nine people, according to the Houthis who hold much of Yemen including the capital Sanaa.

New York-based Human Rights Watch (HRW) said "at least six civilians" were killed in the strikes which "reportedly injured at least 80 others".

The rights group noted that the Hodeida port "is critical for delivering food and other necessities to the Yemeni population".

The damage "could have a long-term impact on millions of Yemenis who rely on the port for food and humanitarian aid", it said.

The strikes "damaged or destroyed at least 29 of the 41 oil storage tanks at Hodeida port, as well as the only two cranes used for loading and unloading supplies from ships," HRW said.

It added that the attack also forced the Hodeida power plant offline for 12 hours.

"The attacks appeared to cause disproportionate harm to civilians and civilian objects. Serious violations of the laws of war committed wilfully, that is deliberately or recklessly, are war crimes," HRW said.

In November the Houthis launched an offensive against Israel-linked ships in the Red Sea, a campaign they have said is meant to show solidarity with Palestinians in Gaza and press Israel to end its war on the destroyed territory.

The Houthis have also launched strikes on other Israeli port towns since the war on Gaza began.

Yemen has been engulfed in a devastating conflict since 2014 between the Houthis and the internationally recognised government, supported by a Saudi-led military coalition.

The fighting has killed hundreds of thousands of people either directly or indirectly and triggered one of the world's worst humanitarian crises.

The Israeli strikes on Hodeida risk worsening conditions for millions of Yemenis in rebel-held areas, HRW said.

"Yemenis are already enduring widespread hunger after a decade-long conflict. These attacks will only exacerbate their suffering," said Niku Jafarnia, HRW's Yemen and Bahrain researcher.

*This story was edited by Ahram Online