GENEVA (Reuters) - Operations at a Red Sea port in Yemen used for aid imports have fallen to about a quarter of its capacity, a UN official said on Tuesday, adding it was not certain that a Gaza ceasefire would end attacks between the Iran-backed Houthis and Israel.

Yemen’s Iran-backed Houthi movement has released the crew of a cargo ship more than a year after its fighters hijacked the vessel in the Red Sea, as part of its campaign of attacks in support of Hamas in its war against Israel.

Four of the port's five tugboats needed to escort the large ships bringing imports had sunk, while the fifth was damaged, a UN official has said.