China Guangfa Bank said it will raise margin requirements for personal deferred gold and silver trading contracts linked to the Shanghai Gold Exchange.

Effective after market close on June 22, the margin ratio for both gold deferred contracts and silver deferred contracts will be increased to 140% from 100%, according to a notice issued by the bank.

The bank said any further adjustments to margin requirements for the contracts would be announced separately and advised investors to manage positions prudently.