LONDON, April 19 (Reuters) - Nickel prices hit their highest since September last year on Friday, driven by worries about tighter supplies from leading exporter Indonesia and market talk China plans to buy the metal for its stockpiles.

Three-month nickel on the London Metal Exchange (LME) was up 3.6% at $19,220 a metric ton by 1313 GMT after hitting $19,440, its highest since September.

Nickel was boosted by market talk that China's stockpiler, the National Food and Strategic Reserves Administration, was planning to buy the metal, used to make stainless steel.

A nickel industry source said the stockpiler was seeking 200,000 metric tons of nickel pig iron, or 20,000 tons of refined metal. The source, who could not be named, said there was no word on how much China would pay.

The National Food and Strategic Reserves Administration did not immediately respond to a request for comment. (Reporting by Polina Devitt, Pratima Desai, Eric Onstad and Beijing Newsroom; Editing by Jan Harvey and Barbara Lewis)