JOHANNESBURG, March 1 (Reuters) - Northam Platinum's CEO said on Friday that platinum mining companies in South Africa, the world's top supplier of the metal, are facing "severe" market conditions and are caught up in the worst crisis in three decades as prices plummet.

"I personally believe it's the worst crisis I have seen in three decades, on a relative basis," said Paul Dunne, the CEO of Northam, South Africa's fourth-largest producer of platinum group metals.

"The squeeze on the industry is severe," he told journalists. (Reporting by Felix Njini; Editing by Nellie Peyton and Jan Harvey)