Saudi airstrikes and warships continue to pound the Yemeni port city of Hodeidah on Monday, with escalating strikes coinciding with Saudi-backed ground forces advancing closer to the city, just three miles from the port itself, according to officials.

This further limits the movement of aid into and out of the vital port, which before the Saudi offensive was the lone source of food imports for 80% of Yemen. Saudi forces control the supply lines, and promises of an aid corridor haven’t panned out so far.

Heavy fighting and Saudi-led encroachment into the area, has aid groups warning that thousands of civilians left in Hodeidah are effectively trapped now. Everyone who lives between the airport and university is effectively trapped inside, and the fighting has almost reached the city’s main hospital, increasing the humanitarian crisis.

The UN reiterated calls for urgent peace talks to prevent the fall of the city, and the famine threatening millions of lives expected to follow. The US called for an immediate ceasefire last week, and there is no sign the Saudi offensive is slowing down.