The deputy prime minister Barnaby Joyce has refused to commit the government to maintain the Renewable Energy Target, after a report that conservative Coalition MPs want to ditch it if the United States pulls out of the Paris climate agreement.

The deputy prime minister ruled out pulling out of the Paris agreement, but criticised “romantic” renewable targets set by states and said MPs were free to think and say what they like about the RET, according to The Guardian.

Australia’s self-imposed target is to achieve 33,000 gigawatt hours of energy from renewable energy by 2020, a target of about 23%. The Abbott government cut the target from 41,000 gigawatt hours in 2015.

On Monday the Australian quoted several unnamed conservative MPs who want to ditch the RET, arguing it would help sharpen the Coalition’s attack on Labor’s plan to lift renewable energy to 50%.

On Monday Joyce was asked on ABC’s AM if he supported dumping the RET and Australia’s Paris greenhouse gas reduction targets, given the US may withdraw from the Paris climate agreement.

“We have an agreement, we’ve signed [it] and we’re honouring that agreement.

However, Joyce said Australia’s needed commitments to be achievable and would “not put undue pressure on our power prices and deliver affordable electricity to the Australian household”.

“That’s why we have an issue with states who go it alone on [renewable energy] targets that are way beyond the capacity for even them to provide, and South Australia is a classic example.”

He said South Australia’s targets were “romantic” and as a result the state “couldn’t get the lights on”.

Despite government claims Australia is on track to meet its Paris commitments, Australia’s emissions are rising and projected to keep doing so, meaning the country will fail to meet its 2030 targets.