The US says it will contribute $100m (£78m) to an international security force in Haiti as violence grips the country.

Heavily armed gangs are demanding the resignation of Haiti’s unelected Prime Minister, Ariel Henry.

Henry was on a visit to Kenya to sign a deal on the deployment of the force when the latest outbreak of violence began earlier this month.

He is currently stranded in Puerto Rico after sustained attacks on Haiti’s international airport prevented him from returning.