Danish lawmakers on Monday reached an agreement to plant a billion trees and convert 10 percent of agricultural land into forests and natural habitats over the next two decades in a bid to reduce fertilizer use.

The government said the deal would lead to "the biggest change to the Danish landscape in 100 years".

"Danish nature will change in a way we haven't seen since the wetlands were drained in 1864," said Jeppe Brus, head of the ministry responsible for implementing the green deal reached in June by farmers, industry, unions and environmental organizations.

Under the agreement, 43 billion kroner (6,2 billion euros) is earmarked for buying land from farmers over the next two decades, the government said.

Denmark's forests are to be increased by 250.000 hectares, while another 140.000 hectares currently under cultivation in climate-damaged lowlands must be converted to forests. In Denmark, 14,6 percent of the land is currently covered by forests.

The government announced in June that from 2030 livestock farmers will be taxed on greenhouse gases emitted by their cows, sheep and pigs, making Denmark the first country to take such a step in combating methane emissions, one of the biggest contributors to global warming up.