(Reuters) - Western Digital Corp said on Wednesday certain materials at two of its manufacturing units in Japan, operated by joint-venture partner Kioxia Holdings Corp, were contaminated and will result in reduced availability of flash storage devices.

According to the company's current assessment, there would be a shortage of at least 6.5 exabytes in flash storage availability. One exabyte equals one billion gigabytes.

Western Digital is working closely with Kioxia to implement necessary measures that will restore the facilities to normal operational status as quickly as possible.

Kioxia, one of the biggest producers globally of flash memory and solid-state storage, is a key supplier to Western Digital. The two companies were in merger talks last year but they reached a standstill.

(Reporting by Yuvraj Malik in Bengaluru; Editing by Krishna Chandra Eluri)