A UN expert says Haiti is in a "race against time," as gangs' control over the capital and the massive displacement of the population deepens the country's crisis.

The Haitian people are suffering gravely at the hands of powerful criminal gangs, while an international security force and local police are badly lacking resources to protect them, a top UN expert said Friday.

O’Neill highlights gangs are expanding into new territories while weapons and ammunition flow into the country

A youth plays with a ring at the end of a wire inside a school where people displaced by gang violence have taken refuge for over a year in Port-au-Prince, Haiti on Sept 20. (AP)

The United Nations' expert on human rights in Haiti said on Friday that the situation in the conflict-hit Caribbean nation had worsened and efforts to rebuild security must be amplified as a security mission deadline fast approaches.