The toll was ruled out by Chancellor Angela Merkel during her election campaign, but supported by the leader of her Christian Social Union (CSU) Bavarian allies, Horst Seehofer.
Seehofer even stated that introducing the charge on foreigners would be a condition of him forming an alliance with Merkel's CDU after the election.
Then on Tuesday, Merkel's transport minister - Peter Ramsauer also from the CSU - spoke out in favour of introducing the toll in Germany's next government.
Asked in an interview with the Bild newspaper how Germany could get much needed investment in its roads he warned against a large expansion of tolls on HGVs (heavy goods vehicles), but supported charges on foreign cars.
“We are preparing to expand HGV tolls on motorways but we must be careful that we do not over do it…I prefer a toll on foreign cars,” he said. Ramsauer estimated the charge on foreigners would bring in €800 million a year.
He added the toll would have to sit alongside more government investment to fill a blackhole in the country's transport network estimated at €7.2 billion a year.
The minister said: “We need both...a guarantee that the budget is going to increase and a toll on foreign vehicles.”
But there is some opposition. The president of the Germany's ecological motor club, Michael Ziesak, said: “Before cars are used to pay for infrastructure maintenance, HGVs should be charged and not only heavy ones.” Smaller HGVs also damage streets, he said. Meanwhile national car club ADAC urged traffic bottlenecks to be upgraded as quickly as possible.
Ramsauer also warned that Germany's government would need to invest considerably more money in the country's infrastructure.
A national transport conference is taking place in Berlin on Wednesday and one government commission has recommended a staggered investment plan in Germany's transport network until 2019, which would fill the €7.2 billion annual hole.
The conference aims to find new sources of investment to repair Germany's worst roads and bridges. Expanding tolls on HGVs is one item up for discussion.
The first €2.3 billion of this cash should be invested in the most urgent road repairs, the commission president and former transport minister Kurt Bodewig told the Ruhr Nachrichten newspaper.
He said it was a “realistic option” which could be achieved within three years. A special investment from government funds of €38.5 billion over 15 years is also being suggested.
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