* Gap between emissions in test and and on-road well known
* Greens lawmaker says assumes minister knew of emissions trick
* Minister Dobrindt rejects claims (Adds minister's remarks, response of Green lawmaker)
By John O'Donnell and Markus Wacket
BERLIN, Sept 23 (Reuters) - Germany's transport minister denied on Wednesday that he had known about the technology Volkswagen (XETRA:VOWG) VOWG_p.DE used to rig emissions tests despite a government acknowledgment only months ago of a general gap between 'test' and on-road emissions.
Volkswagen has admitted using software to recognise when a car was being checked in a test centre.
Spotting for instance when two of a car's four wheels were moving in a test, it could switch the engine to economy mode and inject chemicals to cut emissions in a test below those in normal driving conditions.
Now the focus is shifting to how much the German government knew about the practice, given that it was well documented by independent groups that cars emitted more harmful emissions when in normal use compared to the test centre.
"There is obviously a system of fraud and lies," Oliver Krischer, a Greens party lawmaker who had earlier pursued this issue with the government, told journalists. "I assume that the minister was informed that such manipulative devices were used."
Earlier this year, Krischer and other members of the Green party challenged the government on the discrepancy between emissions in the test environment and during normal driving.
It prompted an answer from the government that showed it was at least aware of such emissions control technology.
Transport minister Alexander Dobrindt hotly denied that he knew of the use of such technology.
"I have made it very clear ... that the allegations of the Greens party are false and inappropriate," he told journalists on Wednesday.
"We are trying to clear up this case," he said, adding that the first he knew about it was when he read it in a newspaper.
Yet the transport ministry had acknowledged in a July 28 statement that it was aware of the issue and that it was seeking tighter rules. It did not, however, recognise any deliberate rigging.
"Through the improvement and reconfiguration of the measurement process, through the fixing of far lower tolerance levels as well as using conditions that are closer to reality, the aim is to get a more representative result," the government said.
It acknowledged that not enough had been done to address emissions control devices and said it was working on new 'technical rules'. The introduction of those rules, it added, was being negotiated with the European Union's executive, the European Commission.