Saudi Arabia on Friday gave the United Nations permission to resume flying aid workers in to Yemen’s capital Sanaa. This comes three weeks after the Saudi-led coalition closed all points of entry – air, land and sea – to stop the Houthi rebels they are fighting from getting arms from Iran, Reuters reported.

However, Riyadh did not allow ships loaded with wheat and medical supplies to dock, a UN spokesperson said.

The move to allow aid workers in comes after the United Nations, on November 8, warned that millions could die in Yemen in the “largest famine the world has seen for many decades” if aid is not allowed to enter the country. The World Health Organization said 3.2 million people will be pushed into hunger, even with the blockade lifted partially.

The coalition gave clearance for UN flights in and out of Sanaa from Amman, Spokesperson for the UN Office for the Coordination of Humanitarian Affairs Jens Laerke said, adding that there was concern about the ships. “We are particularly talking about one ship which is offshore Hodeidah with wheat from the World Food Programme, and another waiting in Djibouti with cholera supplies.”

Unicef is also waiting to ship vaccines, aid officials said.

Major needs include water pumps to help stem a massive cholera outbreak and fuel needed to transport food and goods, AP reported.

Saudi’s action to close all entry points came after it intercepted a missile fired toward Riyadh earlier in November. Iran has denied supplying weapons.