By Theo Leggett
Europe business reporter, BBC News
Many EU members want to see more open energy markets
French finance minister Thierry Breton is confident a merger between Gaz de France and Suez will go ahead even if Brussels raises objections to it.
The European Commission, currently examining the deal, is set to inform both firms on Friday of its preliminary findings, laying out any concerns.
The merger is hugely controversial as it is seen as a political manoeuvre, engineered by the French government.
When it was first unveiled, Suez faced the possibility of a foreign takeover.
Suez, an industrial giant with interests in electricity and gas as well as water, was seen as a bid target for Italian utility Enel.
An all-French merger between Suez and Gaz de France, a key player in Europe's gas markets, would remove that threat - and create a new French national champion in the energy market.
Italian politicians are furious about the proposed deal - and accused Paris of blatant protectionism.
They called on the European Commission to intervene and Brussels responded by opening a formal enquiry in June.
Competition Commissioner Neelie Kroes is concerned that the merger could harm competition in the French and Belgian energy markets - and consumers could lose out.
But in an interview with French newspaper Le Figaro, Mr Breton said he was confident any objections Brussels put forward could be overcome.
"Everyone knows this project is good for European consumers," he told the newspaper.
The case is one of many in Europe at the moment which have focused attention on the future of Europe's single market - and caused tensions between EU Member states.
Spain has attracted criticism for apparently trying to block the takeover of its electricity utility Endesa by German firm E.ON.
And Italy has blocked a takeover of the roads operator Autostrade by a Spanish firm, Abertis.
Thierry Breton has been leading support for the deal
On the one hand, some member states are reluctant to see highly prized national industries fall into foreign hands.
But the Commission, backed by more liberal governments, doesn't want to see new market barriers spring up to replace those which it has spent years pulling down.
Nevertheless, despite its rhetoric, the Commission can do little to prevent deals which protect national interests - provided they do not breach EU competition laws.
In the case of the Gaz de France-Suez, merger Mr Breton clearly believes that competition law will not prove to be a serious obstacle.
In fact, domestic politics in France appear more likely to derail the plan.
The deal would oblige the French government to reduce its stake in Gaz de France from 70% to just 34%
It is a prospect which has provoked a storm of protest in France after ministers promised just two years ago that it would make no further moves to privatise the company.
That promise followed widespread protests and strikes from workers who feared that privatisation would lead to job losses.
The French Parliament is due to vote on the issue next month.
While most analysts now expect the measure to be approved, the debate is likely to be a very stormy one.