Potential showdown brews over cargo ship said to be carrying aid.

The U.S. military and its Saudi allies are preparing for another potential showdown with Iran in the Gulf of Aden over the fate of a cargo ship said to be carrying aid for Yemen. Two Iranian warships have linked up in the waters off Yemen’s coast with an Iranian vessel believed to be carrying humanitarian aid for civilians caught in Saudi Arabia’s two-month-old bombing campaign against Iran-backed Houthi rebels who have seized control of Yemen’s capital and government, Pentagon officials said Tuesday. That has raised concerns that Iran will ignore international pressure and send the ship directly to Yemen without agreeing to United Nations inspections. If Iran defies the U.N. and U.S., it could set the stage for a showdown in which Saudi ships might try to block the flotilla from reaching Yemen. The U.S. military, which has 14 warships at sea in the region, is keeping a close eye on the Iranian ships scheduled to arrive in the western Yemeni port of Hodeida on Thursday, according to Iran’s official Islamic Republic News Agency. American officials have called on Iran to send the ship to the African country of Djibouti to undergo newly established U.N. inspections for aid going to Yemen. But Iran has ignored that appeal so far. Iranian Foreign Ministry spokeswoman Marziyeh Afkham said last week that Yemen aid efforts would be “in full harmony” with the U.N., but she didn’t say whether that meant the ship would go to Djibouti. If Iran refuses to send its aid ship to Djibouti, Saudi and U.S. officials would have to decide whether to try to confront the Iranian flotilla at sea.

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