Anil Ambani-led Reliance Power's board will on July 4 consider merging another group firm Reliance Natural Resources with itself.
A meeting of Reliance Power's board of directors has been called on Sunday to consider the merger, the company said in a statement.
The statement was released after the close of stock market, but speculation about the deal pulled down the shares of both the companies sharply in the last minutes of trading.
While RNRL settled 2 per cent down at Rs 63.65 a share, R-Power managed to close 3 per cent up at Rs 174.50 a piece. In intra-day trade, R-Power had gained as much as 5 per cent, but RNRL fell by over 7 per cent.
While the companies did not disclose any details of the proposed merger, some brokers said that rumours are about a share-swap deal with four shares of RNRL for every one R-Power share.
Currently, the two stocks have market values in the ratio of about 1:3. The two companies together command a market capitalisation of Rs 50,000 crore (Rs 500 bilion).