RNA - The UN Office for the Coordination of Humanitarian Affairs (OCHA) said on Thursday that the vessels were turned back last week en route to Yemen's Hudaydah, which is controlled by the Houthi movement.
The tankers were said to have been carrying just over 71,000 metric tons of fuel, which represents more than 10 percent of Yemen's total monthly fuel needs.
"At a time when Yemen is facing an unprecedented cholera outbreak and millions of its people are at risk of falling into famine, it is essential that all ports remain open and any delays are avoided," said OCHA spokesman Russell Geekie.
It was not clear why the tankers were stopped.
Hudaydah is a "lifeline" for Yemen, a conflict-ridden country that is 80 percent dependent on imports.
A few months ago, Saudi Arabia threatened to attack the port city, with the UN saying it was “extremely concerned” over the potential assault.
On Wednesday, the UN warned that the catastrophic situation in Yemen is turning into a combination of the world’s worst humanitarian crisis amid almost daily Saudi bombardment of the impoverished Arab nation.
More than 1,900 people have died from cholera in Yemen and 400,000 cases have been reported since April, when the outbreak began.
Saudi Arabia has been leading a brutal military campaign against Yemen for more than two years to eliminate the Houthi movement and reinstall Riyadh-friendly former president, Abd Rabbuh Mansur Hadi. The Saudi military campaign, however, has failed to achieve its goals.
The protracted war has already killed over 12,000 Yemenis, with the US and the UK providing the bulk of weapons used by Saudi forces and giving coordinates for airstrikes which have killed many civilians.
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