ACF executive director Don Henry backed the Government's legislation after changes announced on Monday.

The changes include raising the 2020 emissions reduction target range to 25 per cent in the event of strong global agreement, delaying the scheme, and extra help for industry.

While Mr Henry was at pains yesterday to point out the ACF still had serious reservations about the scheme, other members of the ACF hierarchy were taken aback by Mr Henry's support for legislation that included the 25pc target.

The Age was told yesterday the ACF's 40-member council would harden its position against the scheme rather than back it.

The board was not informed of the decision to support the legislation.

Mr Henry said a decision had been made by himself and ACF president Ian Lowe.

"We will be having a discussion with the board at the next sitting in a couple of days," he said.

Mr Henry said the ACF would continue to campaign for tougher targets.

The decision to back the legislation was made because the tough 2020 target would give greater impetus to global climate negotiations.

Rank-and-file members of the ACF have also expressed anger.

Pablo Brait, a 10-year member, quit in protest over the foundation's support for a policy that scientists warned would not prevent runaway climate change.

He knew of others who had taken a similar stance.

Environment groups including Greenpeace, the Wilderness Society and Friends of the Earth have joined pressure group GetUp in opposing the proposed scheme.

The Climate Institute and the WWF support it.