June 22 (Reuters) - Energy Transfer Equity LP, a portfolio company that owns energy assets, said it has made an all-equity offer of $53.1 billion, including debt, to merge with Williams Companies Inc.

Energy Transfer equity said it would buy all of the outstanding common stock of Williams at $64 per share, which represents a 32.4 percent premium to its closing price on June 19.

(Reporting by Ismail Shakil in Bengaluru; Editing by Anupama Dwivedi)