By Agence France-Presse Thousands of tonnes of food aid near Yemen's flashpoint port city of Hodeida is infested with insects and must be fumigated to feed millions of people, the UN said Wednesday. Last month, a team from the UN's World Food Programme visited the Red Sea Mills warehouse for the first time since September, when they became inaccessible due to the conflict between pro-government forces and the Huthi rebels. "WFP carried out a full assessment of the condition of the wheat and laboratory tests confirmed it was infested with insects which has resulted in some hollow grains," said spokesman Herve Verhoosel. "The wheat needs to be fumigated before it can be milled into flour." Before the UN lost access in September the Red Sea Mills held 51,000 tonnes of grain, which was enough to feed more than 3.7 million people for a month. However, Verhoosel said the WFP anticipates the flour yield will be "slightly lower" than normal because of the damage caused by insects. "At this stage, we cannot confirm how much flour we will be able to get from the wheat at the Red Sea Mills," he said. "WFP is awaiting final clearance from the local authorities for a follow-up operation to the Red Sea Mills in order to begin the fumigation and to restart milling operations." The mission follows an agreement struck in Sweden in February, in which Yemeni rivals agreed to redeploy their fighters outside the ports and away from areas that are key to the humanitarian relief effort. The ports are in the rebel-held west of the country, and the agreement especially set out free access to the grain warehouses at Red Sea Mills, under control of the Saudi-backed government forces. Yemen's war escalated in March 2015, when President Abedrabbo Mansour Hadi fled to Saudi Arabia, and a Saudi-backed coalition intervened against the Iran-aligned Huthi rebels. Since then, the conflict has killed around 10,000 people -- most of them civilians -- and has left more than 60,000 wounded, according to the World Health Organization.