Growth in low carbon manufacturing could be stunted by "schizophrenic" government policy on climate change, the Environmental Audit Committee has warned.
The warning follows a government proposed review in 2014 of carbon cutting targets set earlier this year.
The 2014 review could dent investor confidence in low carbon industries, the EAC- Parliament's Green watchdog warned.
Zac Goldsmith MP and member of the EAC said: "The one risk that all investors highlight when they consider putting funds into clean technology is policy change."
"It is therefore absolutely crucial that policymakers recognise that with the stroke of a pen, they can make a good investment bad."
Energy minister, Chris Huhne announced plans for the UK to cut emissions by at least 80% by 2050 this May.
The Fourth Carbon Budget vowed to put Britain at "the leading edge of decarbonisation" through heavy emissions cut backs by 2027.
However, the prospect of a review risked throwing the UK's green intent off course, the EAC warned.
The 2014 review could soften emissions targets if the UK has overachieved on carbon reduction over the next three years.
Joan Walley MP and EAC chair said: "The long term carbon-cutting commitments set out in the Climate Change Act are supposed to provide certainty that Britain is determined to reduce emissions by 80% by 2050."
"Unfortunately, the Government's somewhat schizophrenic attitude to climate change seems to be undermining that confidence."
The EAC also urged ministers to see through proposals to introduce mandatory emissions reporting for all businesses.
Walley added: "Ministers must not row back from the commitment to introduce mandatory emissions reporting by businesses."