The offtake agreement is for the supply of 48,000 metric tons of spodumene concentrate to Canmax from the London-listed Premier's Zulu lithium mine in Zimbabwe. This is in exchange for a $35 million cash injection Canmax made towards construction of the Zulu processing plant.

Canmax had moved to terminate the deal in June after Premier failed to start delivering the lithium concentrate as promised in May and declared force majeure, citing problems at its recently assembled plant.

In separate statements, the two companies said they had agreed to restore the offtake deal.

"The amended agreement restores the working arrangements between Premier and Canmax and therefore the force majeure and default notices have been withdrawn by the respective parties," Premier said.

Canmax confirmed the agreement in a separate statement.

"The amended agreement resumes the cooperation between the company and Premier," Canmax said.

Canmax is also the single biggest shareholder in Premier, with a 13.38% stake and is one of several Chinese firms that have invested more than $1 billion in Zimbabwean lithium assets over the past two years, as they seek to lock in future supplies of the key battery mineral.

Other Chinese firms with lithium mining operations in Zimbabwe include Zhejiang Huayou Cobalt, Sinomine Resource Group, Chengxin Lithium Group and Yahua Group.

(Reporting by Nelson Banya; Editing by Conor Humphries)