The Dutch government brushed aside calls by environmentalists and opposition parties Thursday to drop an appeal against a landmark court ruling ordering it to slash greenhouse gases by a quarter by 2020.

"We are going ahead," Deputy Environmental Minister Wilma Mansveld told lawmakers during a parliamentary debate, despite calls from many opposition parties to abandon or at least amend the plan to appeal.

"We think the court based its decision on a number of points which we're disputing," Mansveld told lawmakers.

A local Dutch judge in June ordered the government to slash emissions by 25 percent by 2020 in a case that could serve as a blueprint for environmental activists around the world.

Climate experts hailed the judgement as a "milestone" case, which was brought to court by 900 individuals. Experts say it would encourage concerned citizens in other countries to take their own governments to court to force them to cut the gases blamed for global warming.

"This was a historic judgement. The government has a duty to comply," Liesbeth van Tongeren, lawmaker for the leftist environmental party GroenLinks told parliamentarians.

She suggested that the case should be referred to the Dutch highest Supreme Court, the Hoge Raad, for a final decision.

The Supreme Court however can only rule on the legal merits and motivation for the judgement and not on the substance of the case.

"We want to have contents of the case re-examined," Dutch Economics Minister Henk Kamp said.

In its far-reaching ruling, The Hague's District Court said current Dutch policy is to reduce emissions by 17 percent by 2020, which was less than the international norm for industrialised nations.

But Kamp disputed this, saying in actual fact emissions are to be reduced by 21 percent in five years' time.

"That means that we'll only be four percent short (of the target)," he said.

Environmentalists staged a small protest outside parliament earlier Thursday which included a giant inflatable dinosaur whose body parts were made to represent carbon-spewing cars, truck and planes.

One of its feet was in the shape of an oil rig.

"Parliamentary debates like these are really important to focus the attention on the issue," demonstrator Victor van de Belt, 54, told AFP.

"The Netherlands is falling behind in its commitment to the planet," he said.