The European Competition Commissioner Karel Van Miert is thought to have rejected a request to refer the bid back to London and is set to give regulatory clearance as early as today.
Earlier this month the Department of Trade and Industry asked for authority for vetting the deal to be handed to UK competition authorities on two grounds - public interest concerns and the impact the takeover would have on competition in the UK electricity market.
EdF already supplies about 7 per cent of the UK electricity market through the cross-Channel interconnector, so a takeover of London would amount to vertical integration.
Mr Battle said: "We have a set of concerns about any company which is vertically integrated. We would hope that the merger would fall also within the ambit of our own regulatory structures."
DTI officials said they would expect the Commission's mergers task force to take UK concerns on board. But they refused to comment further on what action the UK could take, saying the department wanted to wait for formal confirmation of the Commission's decision.
This would be the first time that Brussels has ignored a request from a member state to hand back a merger on grounds of national interest. It would also be the first time that is has rejected a request from the UK based on concerns about competition in a distinct market.
The Commission had already taken the unprecedented step of waiving its own rules to allow EdF to launch an unconditional bid for London.
Meanwhile, Mr Battle refused to give a guarantee that the Government would meet its target date of reforming the UK's electricity trading pool by April 2000. The reform processis bogged down by disputes .