Hitachi exercised its option to buy the stake in the venture formed from ABB's Power Grids business in 2020.

"ABB does not expect to record any significant gain or loss as a result of the sale. ABB expects net positive cash inflows of approximately $1.425 billion upon closing of the sale," which is set to close before the end of the year, pending regulatory approvals, it said in a statement.

"We are delighted to have agreed on the final part of the transaction earlier than expected and on favorable terms. This will further strengthen our balance sheet and give us additional flexibility in our capital allocation decisions," ABB finance chief Timo Ihamuotila said.

(Reporting by Michael Shields; Editing by Mark Potter)