May 8 Toshiba Corp will offer to buy Alstom's power grid business for "several hundred billion yen" if General Electric Co completes its planned purchase of Alstom's energy business, the Nikkei newspaper reported.
GE has offered to buy Alstom's energy business, which makes power generation systems along with power grids, for about $16.9 billion.
The French company said last week it was reviewing GE's offer but has also given Germany's Siemens AG until the end of May to make a rival bid.
A spokesman for GE declined to comment on the Nikkei story. (Reporting by Ankit Ajmera in Bangalore; Editing by Saumyadeb Chakrabarty)