TOKYO, May 29 (Reuters) - A global aluminium producer

has offered Japanese buyers a premium of $145 per metric ton for

July-September primary metal shipments, down 20% from the

current quarter, two sources directly involved in quarterly

pricing talks said on Thursday.

Japan is a major Asian importer of the metal and the

premiums for primary metal shipments it agrees to pay each

quarter over the London Metal Exchange (LME) cash price

set the benchmark for the region.

For the April-June quarter, Japanese buyers agreed to pay a

premium of $182 per ton , down 20% from the prior

quarter.