European governments are expected to decide at a meeting Dec. 5-6 whether to adopt a policy that would all but prevent them from using non-European rockets.

The issue is expected to be the most hotly debated topic as European Space Agency (ESA) government ministers meet in Berlin to set European space spending priorities in the coming years.

The French government — the biggest investor in Europe’s Ariane 5 rocket and the principal European backer of a program to adopt Russia’s Soyuz vehicle for use at Europe’s spaceport in South America — is backing the proposal. Opposition is expected to come from the British and German governments, which are less heavily invested in launch vehicles and want to preserve their right to seek low-cost launch options wherever they may be found.

European governments have long been urged by ESA policy to give a preference to European products in their choice of launch vehicles. In recent years, no large European government satellites have been launched by non-European rockets except when they were part of a bilateral program.

But small scientific and Earth-observation satellites financed by individual governments have routinely used Russian, Ukrainian and Indian vehicles as these rockets have become available. It is this practice that would be prohibited, except in exceptional circumstances.

The policy’s goal is to create in Europe a situation similar to what exists in the United States: U.S. government spacecraft are by law obliged to use U.S. rockets.

French Research Minister Francois Goulard, who will lead the French delegation to the Berlin conference, said Nov. 29 that he wants to put into place a clear “European purchase policy” for launch services.

Goulard made his remarks during a press briefing to celebrate the 25th anniversary of the Arianespace commercial launch consortium. ESA Director-General Jean-Jacques Dordain confirmed at the press briefing that the buy-European policy would be one of six resolutions to be presented to the Berlin meeting. He declined to provide details.

Smaller satellites built for scientific, technology research or Earth-observation missions have sought less-expensive, non-European vehicles to stretch their budgets.

The French space agency, CNES, has contracted to use the Russian-Ukrainian Dnepr launch vehicle for Myriade, its new multipurpose satellite platform. The British government recently used Russia’s Cosmos rocket for an Earth-observation satellite. The German government has used Cosmos and the German-Russian Rockot vehicle for its small satellites. ESA itself has been drawn to Rockot for its smaller Earth-observation missions.

The buy-European rule would not be fully enforced until Europe’s full line of vehicles — the heavy-lift Ariane 5, the medium-lift European version of Russia’s Soyuz rocket and the Italian-led Vega launch vehicle — is in place. Ariane 5 is operational, but the Soyuz and Vega vehicles to be operated from Europe’s Guiana Space Center in French Guiana will not be ready before 2008 or 2009.

One French government official said the rule would include guarantees that European governments do not pay much more for using European vehicles than they would if they sought launch services on the open, global market. In addition, launches that are part of bilateral cooperation accords — for example, the U.S.-French Jason-1 and Jason-2 ocean-monitoring satellites — would be exempt from the rule.

The French government official explained the policy this way: “The point is this: Are we in Europe going to be actors in this sector or merely spectators? If we are actors then we need to protect our launcher sector, an area we all agree is strategic. And the fact is, ESA has performed a study showing that the difference in price between using a European or a non-European vehicle is very small when total mission costs are examined. So we’re not talking about something that would seriously affect the feasibility of a mission.”

European industry officials said one reason for the buy-European policy is the current status of the Italian-led Vega small-satellite launcher.

When the contracts relating to Vega’s development and operations from Europe’s Guiana Space Center were signed in 2003, Vega backers agreed that the rocket would be developed to be able to sell a launch for no more than 18.5 million euros ($22 million).

Vega is designed to place payloads weighing 300 to 2,000 kilograms into low Earth orbit.

The ministers at the ESA meeting in Berlin will be asked to approve a Vega support program that calls for five demonstration launches financed by European governments. Industry officials said the backing is needed because Vega will not be commercially viable or attractive to government customers during its early missions without further government aid.

Peter B. de Selding was the Paris bureau chief for SpaceNews.