Labor's 40 climate meeting in six weeks

The federal opposition has kicked off a series of 40 meetings with business, unions and environment groups over six weeks to discuss its ambitious plan to slash carbon emissions.

Labor announced its proposed post-2020 emissions reduction target of 45 per cent by 2030 - recommended by the government-funded Climate Change Authority - at the end of 2015.

However, the policy isn't set in stone and environment spokesman Mark Butler told ABC on Thursday he'll take it to several stakeholders before assessing if it's consistent with targets of comparable nations.