A UN rights expert on Thursday urged Kuwait to abolish its "kafala" system for foreign workers which has long been criticised.
Under the system, domestic workers are forced to work long hours, mistreated and beaten, prompting hundreds to flee every year, said Maria Grazia Giammarinaro, a UN special rapporteur on people-trafficking.
"The kafala system... creates a situation of vulnerability which favours abusive and exploitative work relationships," she said.
The kafala system restricts workers from moving to a new job without their boss's consent before their contracts end, leaving many trapped.
Human Rights Watch and other groups have documented widespread abuses under the system, including non-payment of wages, long working hours with no rest days, physical and sexual assault, and no clear channels for redress.
Kafala should be "replaced by a different regulation allowing migrant workers to enjoy substantial freedom in the labour market," Giammarinaro said at a news conference after a five-day visit to Kuwait.
She welcomed a number of "positive" developments in the oil-rich state, including the opening of two government-run shelters for female domestic workers who leave their employers.
In July, Kuwait became the first Gulf state to set a minimum wage for its hundreds of thousands of mostly Asian domestic workers.
In its 2016 "Trafficking in Persons" report, the US State Department upgraded Kuwait from tier three, the worst level, to tier two while keeping it on watch list, citing an improvement in its treatment of migrant workers, including maids.