(Adds quotes from de Palacio, German Transport Minister, German can recycling system, Austrian truck ban)
By Lisa Jucca
BRUSSELS, July 23 (Reuters) - The European Commission began investigating on Wednesday Germany's plan to offer the country's truckers 600 million euros ($684.3 million) in government subsidies to compensate for a new road toll system.
The probe was launched as the Commission unveiled an EU-wide proposal to use road tolls on trucks in environmentally sensitive areas to help pay for rail lines and reduce lorry traffic.
"The Commission decided to further investigate the German plan to compensate road hauliers for the higher financial burden resulting from the future increase of the toll rates," the European Union executive said in a statement.
European Transport Commissioner Loyola de Palacio said the state aid probe would suspend the launch of the German road toll system for commercial vehicles on August 31, from which cash-strapped Germany is expecting yearly revenues of 2.8 billion euros.
But German Transport Minister Manfred Stolpe said in Berlin the implementation of the toll system on August 31 was not in danger, adding the ministry welcomed the EU decision.
Haulage firms fear the system would cost each truck an additional 150 euros to cross Germany, a key transit EU route for freight. The Commission was also concerned that aid such as lower excise duties for German hauliers would be unfair to non-German firms.
The Commission refrained, however, from acting against a German system of taking deposits on recycling cans on the same day of the probe following political pressure from Germany.
Informally, Commission President Romano Prodi asked Chancellor Gerhard Schroeder to immediately suspend the deposit system in view of an EU-compatible scheme starting in October, Commission spokesman Jonathan Todd told reporters.
The Commission wanted Berlin to hold off in introducing its road toll system to allow it to examine its pan-EU scheme.
De Palacio's road toll proposal would allow countries such as Austria to charge extra for trucks using its Alpine passes and tunnels to pay for the building of alternative rail links with Italy through the scenic mountain region.
"We are not trying to penalise road transport, we are trying to encourage other forms," de Palacio told a press conference.
"If you start beating the road lobby, you're going to undermine competitiveness in Europe and lose jobs. We want everything to work."
Green groups have criticised the move as insufficient because it limits such "cross subsidies" to environmentally sensitive areas, caps the amount that can be charged and applies only to truck tolls and not to cars.
At present EU countries can only levy charges that reflect the cost of building and maintaining motorways and are not allowed to "cross-subsidise" by charging road users to pay for railways.
The change would be of particular interest to Austria, which lost an EU court case in 2000 for over-charging trucks to pay for a rail link through the Brenner pass.
Austria has also banned trucks weighing more than 7.5 tonnes from driving through its pristine Tyrol region. But the Commission decided to challenge this measure in court on Wednesday.
The EU proposals, which reflects a gradual move towards road tolls in all EU countries, would make it possible to add 25 percent to truck tolls in areas such as the Alps and the Pyrenees to subsidise rail links.
It would also allow countries to vary road tolls to ease congestion or to take into account noise pollution, for example by charging more at rush hours or along stretches of highway that are close to residential areas.