More than 8,000 Glencore coal workers will be forced to take annual leave as the mining giant shuts down its Australian coal operations due to an oversupply of the commodity.

Glencore will shut down all of its 20 coal mines across NSW and Queensland from mid-December, cutting production by five million tonnes. Annual leave will be imposed on employees over the Christmas period, and leave will be brought forward for those employees who have low holiday balances. Hundreds of employees…