The United Nations paused flights to Haiti's capital last Tuesday, a day after gangs struck three commercial planes with gunfire, prompting the US aviation regulator to ban US airlines from flying to the conflict-ravaged Caribbean nation for 30 days.
"UNHAS provides passenger and light cargo transport in Haiti for the entire humanitarian community, including local and international NGOs," the World Food Programme said in a statement, adding that the suspension had not affected food supplies.
Haiti's government helicopter also resumed services on Monday, transporting three new government ministers following a cabinet shake-up last week that saw the prime minister ousted and many of his top ministers replaced.
Even as the flights restarted, armed violence continued in parts of the capital Port-au-Prince such as Lower Delmas.
The majority of Port-au-Prince is under the control of armed gangs who have been making gains in recent weeks while a long-delayed partially deployed UN-backed mission to reclaim territories and ensure aid deliveries continues to stall.
On Sunday, UN migration agency IOM estimated more than 20,000 people were displaced across the capital in four days, marking the largest mass displacement in over a year.
"The isolation of Port-au-Prince is amplifying an already dire humanitarian situation," the IOM Haiti chief Gregoire Goodstein said in a statement, adding that only 20 per cent of the capital was accessible to humanitarian workers.
"Our ability to deliver aid is stretched to its limits. Without immediate international support, the suffering will worsen exponentially," he said.
UNICEF Haiti chief Geeta Narayan said more than half of the 20,000 displaced were children, who were facing the "compounded impacts of malnutrition, cholera outbreaks, severe psychological distress, and all too often, tragic loss of life".
The IOM estimated that as of early September over 700,000 people had been internally displaced in the country, while the IPC, a benchmark index of food insecurity, has reported worsening shortages with some 6000 people facing famine-level hunger.
