More than 33,000 people fled Port-au-Prince this month as the Haitian capital was overrun by well-armed gangs triggering political chaos in the impoverished Caribbean nation, the United Nations has said.

Gang "attacks and generalized insecurity are pushing more and more people to leave the capital to find refuge in provinces, taking the risks of passing through gangs-controlled routes," the UN's International Organization for Migration said in a statement late Thursday.

From March 8-20, observers counted "the movements of 33,333 people leaving" the capital area.

It "should be emphasized that provinces do not have sufficient infrastructures and host communities do not have sufficient resources that can enable them to cope with these massive displacement flows coming from the capital," the IOM said.

The country has been rocked by violence since late February, when gangs launched a coordinated offensive, raiding a prison to release thousands of inmates, and demanding the resignation of Prime Minister Ariel Henry.

Henry, stranded outside the country after the violence shut down the main airport, has since agreed to step down and allow the formation of an interim government. But negotiations have been slow despite pressure from neighboring Caribbean countries and the United States.

According to the International Crisis Group, the attempts to forge a political compromise face major headwinds, because "gangs have already signalled that they will not recognize the coalition government that is expected to be formed in the coming days."