The waivers, amendments and relief are effective immediately.
In January, major shareholder Resource Capital (RCF VI) also provided a standby equity facility of up to £25mln to strengthen the balance sheet during the ramp-up of the processing plant at the Drakelands mine.
The facility is required to be approved by shareholders for the waiver letter to remain effective.
Russell Clark, Wolf’s managing director, said: "The company welcomes the continued support from its lenders, UniCredit Bank, London Branch, ING Bank and Caterpillar Financial.
“The combination of the waivers and relief from the Letter and the funding support from RCF VI enables the company to focus on the success of Drakelands.
“The company will now seek the required regulatory and shareholder approvals to confirm this support."