New Interior Secretary Ryan Zinke (2nd from R) rides on horseback with a U.S. Park Police horse mounted unit while reporting for his first day of work at the Interior Department in Washington, U.S., March 2, 2017. (Reuters)

The Interior Department’s budget would be slashed by nearly $2 billion compared with last year’s budget, according to a proposed spending plan from the Trump White House.

A proposed 12 percent decrease to $11.6 billion would cause pain in the offices that purchase public lands. That part of Interior would lose $120 million in funding under the proposal. Money for National Heritage Areas would be eliminated. The budget synopsis was not clear about whether that includes National Historic Parks, such as the Chesapeake & Ohio Canal in Virginia and Maryland.

After his confirmation this month, Interior Secretary Ryan Zinke said in an address to his staff that he had seen the White House’s budget proposal, disagreed with what was then thought to be a 10 percent budget cut and would express his displeasure.

“I looked at the budget. I’m not happy, but we’re going to fight about it, and I think I’m going to win at the end of the day,” Zinke said.

It appears he failed; President Trump’s proposed cut is even higher. Interior’s budget has grown steadily since 2012 to $13.1 billion. Trump’s proposal is about $100,000 lower than what Congress granted the agency five years ago.

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Interior employs 70,000 people at more than 2,000 locations to fulfill its mission, managing 530 million acres — 20 percent of U.S. territory. It controls even more resources underground, 700 million acres of minerals.

The budget synopsis said the White House will increase funding for extracting energy on land and offshore but does not provide a figure. It promises to make sure taxpayers get a fair return on revenue from energy development but does not cite a percentage.

According to the synopsis, funding cuts to major land acquisition will be diverted to national parks, which have a maintenance shortfall of more than $12 billion. There was no indication of how the Trump administration will attack that problem, which Zinke listed as his top priority at his confirmation hearing.

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Land-acquisition funding has enjoyed bipartisan support in Congress because it protects national parks from harm.

Large parcels of land inside parks are privately owned, said John Garder, director of budget and appropriations for the National Parks Conservation Association. When owners sell, parks can work to acquire the land.

In President Obama’s last budget, funding of $2 billion was requested for coastal resilience. Obama asked for $24 million more for land acquisition than the $324 million Congress provided in 2016.

Heritage area funding is important, Garder said, because it supports tribal preservation officers and provides grants to underrepresented communities.

The synopsis provided by the White House offers little information about the fate of key Interior programs, such as the Climate Action Plan, which helps vulnerable coastal communities such as Miami prepare for the impact of sea-level rise and other effects of climate change.

An earlier version of this article said the proposed budget cuts would eliminate National Historic Sites. They would eliminate National Heritage Areas.