The United States has barred imports from Malaysian glovemaker Supermax Corp over alleged forced labour practices at the company, the fourth Malaysian firm to face such a ban in the past 15 months.

Malaysian factories - which make everything from palm oil to medical gloves and iPhone components - have increasingly come under scrutiny over allegations of abuse of foreign workers, who form a significant part of the country's manufacturing workforce.

The US Customs and Border Protection (CBP) issued a...