UPDATE 18/05: The Abbott government has ditched plans for two-yearly reviews, in a move that should see changes to the RET passed by parliament within weeks.

ORIGINAL 13/05: Last week it looked like the RET was set, now it is up in the air again.

On Friday Labor gave in principle support to a new reduced Renewable Energy Target of 33,000 gigawatt hours (GWh), in what looked like the last step toward a bipartisan agreement.

But the Opposition now says it will not support a deal that includes reviews every two years.

It is also opposed to another Coalition addition – the inclusion of native wood burning as a renewable energy source.

ALP environment spokesperson, Mark Butler, says constant reviews of the RET would stifle investment and industry certainty.

“Unless the government drops that, this deal cannot proceed,” he told reporters.

While Labor says it is against the burning of native forests as a renewable energy measure, the reviews appear to be the main sticking point.

“I thought we had a position of agreement based on the 33,000GWh large scale target. What the government should do is drop this silliness of re-arguing the case on the reviews, which were dropped months before,” Butler said.

“Get back to the real game, which is to find a revised large-scale renewable energy target, which we have agreed can be 33,000GWh, put it into the parliament, and let the industry get back on with building new projects and creating new jobs.”

The Clean Energy Council (CEC) has withdrawn its support for the RET as well.

CEC chief executive Kane Thornton has told News Corp reporters that the retention of a review every two years is a “deal-breaker”.

The CEC was pivotal in brokering the 33,000GWh deal, and its withdrawal of support is expected to have influenced Labor’s current position.

Andrew Thomson, managing director of internat­ional green power company ACCIONA Energy, has called on the government to reconsider the review policy.

“A 2016 review of the Renewable Energy Target would be the fourth major government inquiry into renewable energy since the federal Coalition was elected to government in September 2013,” Mr Thomson told The Australian.

“ACCIONA is a global renewable energy business.

“As an international investor, we look for policy stability in assessing which countries are the best place to invest. Having ­numerous, repetitive reviews only serves to create … risk and uncertainty.”

In March, the government said it opposed the biennial reviews and pledged to remove them.

“We will also remove the requirement for regular two-yearly reviews of the RET to give the industry the certainty it needs to move ahead,” a joint press release by environment minister Greg Hunt and industry minister Ian Macfarlane said.

Just a few weeks later, it is willing to risk the deal entirely by going against a previous promise.

It appears that progress will be slow even if the major parties can sort their differences, with Greens Senators saying they are opposed any reduction of the RET.

It means the Government must win the support of six of the eight remaining cross-benchers.

The RET deal is causing turmoil within the Coalition too.

Reports say one party member told a meeting this week that he was against the target as it would lead to the construction of unnecessary wind turbines, while the other raised fears that wind turbines have adverse health effects.