Abstract: The present invention is directed to a process for forming a high-cis polydiene. The process includes catalyzing a diene polymerization, and terminating the polymerization with a termination mixture comprising an inorganic base and at least one of an amine and a carboxylic acid. The catalyst system is a mixture of (a) organoaluminum compounds; (b) organonickel compounds; and (c) fluorine-containing compounds. The use of an inorganic base reduces the amount of more expensive amine necessary to effectively terminate the polymerization as well as reducing the corrosion in the reaction container. The use of an inorganic base with a carboxylic acid results in a very low gel content as well as reducing the corrosion in the process systems.