Farmers and conservationists will have to “learn to do more with less” ahead of expected deep budget cuts to the Department for Environment Food and Rural Affairs (Defra), the environment secretary has said.

Steve Reed said that Labour would continue to prioritise the restoration of the nature in England, but acknowledged that the chancellor’s budget would be “difficult”.

Speaking to the Guardian on the fringes of Cop16 in Colombia on the eve of Wednesday’s statement by the chancellor, the environment secretary said that the flagship nature-friendly farming scheme would continue to receive backing from the government despite expected cuts to its budget.

He said expected growth in housebuilding would generate much-needed funds through the government’s biodiversity net gain (BNG) initiative, which forces all new building projects to achieve a 10% net gain in nature or wildlife habitat.

“The prime minister and chancellor have been very clear this is going to be a difficult budget, right across the board,” he said when asked what expected cuts would mean for farmers and environmentalists. “We all are going to have to do more with less. I think that’s right because you should always look at how you can use any resource you’ve got more efficiently and effectively.”

On Tuesday, the Guardian reported that Defra was likely to see particularly severe cuts in Wednesday’s budget, and that the reductions will largely fall on nature and flood protections. Defra has historically fared worse than other departments in times of austerity, with the environment budget declining by 45% in real terms between 2009/10 and 2018/19, according to Guardian analysis.

Reed said that the government would begin consulting on a land use framework so the country to improve food security while meeting the government’s target to protect 30% of land and sea.

“The UK is one of the most nature-depleted countries in the world,” he said. “So that matters, because nature underpins everything. It underpins tomorrow’s budget, it underpins the economy, it underpins health, it underpins food, it underpins society as we know it. Without nature, there is no life.

“So the fact that we are an outlier in that respect should concern all of us.”

Asked whether planned investment in the economy in Wednesday’s budget would come at the expense of the natural world, Reed said that the government’s nature-friendly farming scheme – which is known as the Environment Land Management Scheme (ELMS) and pays farmers to create wildlife habitats – would remain the government’s “main lever” to protect nature.

“It’s a world-leading scheme today. We supported it when it was introduced. It will still be a leading scheme tomorrow,” he said, adding they would look to find other sources of funding from the private sector.

The environment secretary also committed to a consultation on a land use strategy in England to meet an international commitment to protect 30% of land and sea by 2030, the headline commitment of this decade’s UN agreement to halt the destruction of biodiversity.

“We have a relatively small amount of land for the size of our population and the many demands that we make of that land,” he said. “We will be publishing the land use framework initially as a consultation document, but it will be looking at how we balance the many different demands that we make of our land, particularly from the different perspective ensuring that we remain food secure, so we have enough land available for growing the food that we need, but also enough land to help nature recover and to meet our demanding but achievable 30 by 30 targets.

“By being much more explicit within the framework about how we’re going to ensure we meet all of our objectives, including nature’s recovery, we have a much better chance of achieving it,” he added.