The EU's "focus group on electro-mobility" was set to adopt a standard type of plug for recharging European manufactured electric cars by 31 March, but an argument between rival designs scuppered agreement.
Sources close to the group told EurActiv that the French and Italians had expressed misgivings over the German design of plug.
The German plug was expected to be adopted as standard, but the French and Italians blocked it because it lacked safety "shutters", used in some countries to protect children from accidental shocks from domestic plugs.
At stake for the winning design is not simply the manufacture of the plug itself, but also a perception that the winning jurisdiction will have home advantage with regard to standards for electric cars.
Some of the world's largest car manufacturers are set to roll out electric car lines in Europe, including German-based BMW Group and Daimler, France's Renault, Italy's Fiat and Micro-Vett, and also foreign-based companies such as Nissan.
A commentator close to the focus group, who preferred not to be named, said: "It [the dispute] is very regrettable and it is clear that industrial interests are at stake."
The focus group comprises members of the European committees for standardisation and for electro-technical standardisation, and also includes Commission personnel and industry specialists.
A report by the group to the Commission – expected next month – is now likely to recommend that the differing national standards which underlie the shutter dispute should be appraised, in an attempt to settle the matter.
Commission aware of disagreements
A spokesman for the EU's Industry Commissioner, Antonio Tajani – who tasked the group with agreeing the standard by the end of the summer – said that the Commission was aware of the disagreement and was watching developments with interest, but remained hopeful that the deadline could still be met.
The argument is likely to cause a delay of several months, and comes at an embarrassing moment as the Commission last week launched its 'Green eMotion' initiative.
The project aims to promote the use and manufacture of European electric cars and has been budgeted at €42 million, of which the EU says it will contribute up to €24 million.
A Commission spokesman stated on the launch that standardisation is "the key factor for a fast and cost-efficient European roll-out of electro mobility".
Under the initiative there will be more than 10,000 charging spots – where electric cars can fill up with power – within participating regions, including Rome and Berlin.
At the launch of the project in Brussels last week, Siim Kallas, the Commission's vice-president responsible for transport, jovially agreed to ensure that one of the first charging stations in Belgium would be built outside the Berlaymont building in Brussels, in the parking space reserved for commissioners' official cars.
As things now stand, there is no agreement in sight as to what kind of plug would used at such a station.
Although the German plug lacks shutters, it does have safety features controlled by the electronic systems in the car and the charging post, which are designed to make the plug inactive unless it is in use with an electric vehicle properly connected.
One member of the focus group, who preferred not to be named, said: "They [the Italians and French] argue: 'What if a child stuck a nail into the plug?' You may as well ask: 'What if a meteorite hit the child before the child stuck a nail in the plug?' so unlikely is that eventuality."
A commentator close to the French side of the argument said on condition of anonymity: "This is not about the technology. It is just that there are rules to be obeyed. Shouldn't companies usually abide by the rules? Is that not what usually happens in Germany?"