The CNE, while approving E.ON’s E26 billion all-cash bid, has imposed an onerous set of conditions that will involve E.ON divesting almost a third of Endesa’s generating capacity.

This has led some observers to question whether E.ON will push on with the deal, while the EU has threatened the Madrid authorities with legal action for imposing terms that it views as tantamount to a restriction of trade.

Now the AFX news agency cites comments by officials at Endesa, saying that the Spanish firm may appeal against the CNE’s ruling on behalf of E.ON. Endesa apparently feels that E.ON would need to dismantle its entire domestic business model in order to comply with the regulator.

Meanwhile, a Spanish financial website has quoted unnamed sources saying that Gas Natural, the Barcelona-based gas company vying with E.ON for control of Endesa, will not be raising its offer to match the German company, and speculates that Gas Natural has admitted defeat in the long-running takeover saga.