ABB is in talks with Hitachi and Mitsubishi Electric to sell all or part of its power grid business, according to Reuters. At the same time, the Swiss company has also started talks with China's State Grid, with CEO Spiesshofer due to meet senior executives during a visit to China this week.

ABB hopes to announce a deal by the end of next week, the sources said.

ABB estimates the business is worth about $15 billion, although analysts estimate it could be around $11 billion, with proceeds likely to be returned to shareholders through a new share buyback and used to accelerate the acquisition of ABB's business automation unit.

ABB declined to comment by press time.

ABB last month launched a process for the sale of its grid business, which includes the manufacture of power transformers and substations for long-distance transmission. The decision to sell the grid business represents a shift from Spiesshofer, who had decided two years ago to keep the grid business despite calls from some shareholders for a sale.