Trading house Sojitz Corp. is in talks with Australian mining company Lynas Corp. about a tieup on the supply of rare earth metals, sources said Wednesday.

The move comes at a time when Japan is trying to diversify its sources of rare earths following stalled exports from China, which currently accounts for about 97 percent of the world's rare earth supply.

Sojitz is expected to obtain from Lynas, which exploits mineral resources in the western part of Australia, the right to buy about 8,500 tons of rare earth metals annually for 10 years, an amount equal to nearly 30 percent of annual demand in Japan, the sources said.